Methods and systems for enhancement of positioning related protocols

ABSTRACT

Methods and techniques are described for enhancing positioning related protocols in order to indicate when one location session is different from another location session. One or more messages provided in a location session by a location server to a user equipment (UE) may include a session indication, such as a session identifier (ID), where a different session ID is provided for each location session. The session indication may be a new session indicator provided in an initial message in a location session or an end session indicator provided in a final message in a location session. An extra message may be sent by the location server indicating that the location session has ended. A correlation ID provided by a network entity to the location server may be included in messages as the session indication, e.g., where a different correlation ID is provided for each location session.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application claims the benefit of U.S. Provisional Application No.62/730,503, entitled “METHODS AND SYSTEMS FOR ENHANCEMENT OF POSITIONINGPROTOCOLS,” filed Sep. 12, 2018, which is assigned to the assigneehereof and which is expressly incorporated herein by reference in itsentirety.

BACKGROUND Field

The present disclosure relates generally to communication, and morespecifically to techniques for supporting location services for userequipments (UEs).

Relevant Background

It is often desirable to know the location of a mobile station such as acellular phone. For example, a location services (LCS) client may desireto know the location of a mobile station in the case of an emergencyservices call or to provide some service to the user of the mobilestation such as navigation assistance or direction finding. The terms“location”, “location estimate”, “position”, “position estimate” and“position fix” are synonymous and are used interchangeably herein.

During a location session, a location server (LS) and a mobile station(MS), sometimes referred to as a user equipment (UE), may exchangemessages defined according to a positioning protocol in order tocoordinate the determination of an estimated location. One positioningprotocol is the LTE Positioning Protocol (LPP) defined by 3GPP in 3GPPTechnical Specification (TS) 36.355. An LPP positioning session may beused by the LS and UE to obtain location related measurements or alocation estimate or to transfer assistance data. An LPP positioningsession may comprise one or more positioning transactions, eachinvolving the exchange of one or more LPP messages between the LS andthe UE. Each LPP message may contain information specific to one or morepositioning methods and/or information common to all positioningmethods. For an LPP positioning session initiated by an LS, the LS willtypically be aware of the start and end of the LPP positioning session.However, the UE may not always be aware of the start and/or the end ofan LPP positioning session, which may cause ambiguity for the UE indistinguishing one LPP positioning session from another or knowing whento cease supporting an LPP positioning session. Removing such ambiguitymay be desirable, e.g. to avoid unforeseen consequences such asreservation of UE storage or provision of UE measurements for an LPPsession that has ended.

SUMMARY

Methods and techniques are described for enhancing positioning relatedprotocols (e.g. LPP or a NAS transport protocol used to transport LPPmessages) in order to indicate when one location session is differentfrom another location session. One or more messages provided in alocation session by a location server to a user equipment (UE) mayinclude a session indication, such as a session identifier (ID), where adifferent session ID is provided for each location session. The sessionindication may be a new session indicator provided in an initial messagein a location session or an end session indicator provided in a finalmessage in a location session. An extra message may be sent by thelocation server indicating that the location session has ended. Acorrelation ID provided by a network entity to the location server maybe included in messages as the session indication, e.g., where adifferent correlation ID is provided for each location session.

In one implementation, a method for supporting location services for auser equipment (UE) performed by the UE includes receiving an initialmessage for a first location session and a first indication of the firstlocation session from a network entity; receiving a final message forthe first location session and a second indication of the first locationsession from the network entity; and receiving an initial message for asecond location session and an indication of the second location sessionfrom the network entity, wherein at least one of the second indicationof the first location session and the indication of the second locationsession indicate that the second location session is different from thefirst location session.

In one implementation, a user equipment (UE) for supporting locationservices for the UE includes at least one wireless transceiverconfigured to wirelessly communicate with at least one wireless network;memory configured to store instructions; and at least one processorcoupled to the at least one wireless transceiver and the memory, the atleast one processor configured by the instructions stored in the memoryto: receive via the at least one wireless transceiver an initial messagefor a first location session and a first indication of the firstlocation session from a network entity; receive via the at least onewireless transceiver a final message for the first location session anda second indication of the first location session from the networkentity; and receive via the at least one wireless transceiver an initialmessage for a second location session and an indication of the secondlocation session from the network entity, wherein at least one of thesecond indication of the first location session and the indication ofthe second location session indicate that the second location session isdifferent from the first location session.

In one implementation, a user equipment (UE) for supporting locationservices for the UE, the UE includes means for receiving an initialmessage for a first location session and a first indication of the firstlocation session from a network entity; means for receiving a finalmessage for the first location session and a second indication of thefirst location session from the network entity; and means for receivingan initial message for a second location session and an indication ofthe second location session from the network entity, wherein at leastone of the second indication of the first location session and theindication of the second location session indicate that the secondlocation session is different from the first location session.

In one implementation, a non-transitory storage medium including programcode stored thereon, the program code is operable to configure at leastone processor in a user equipment (UE) for supporting location servicesfor the UE, includes program code to receive an initial message for afirst location session and a first indication of the first locationsession from a network entity; program code to receive a final messagefor the first location session and a second indication of the firstlocation session from the network entity; and program code to receive aninitial message for a second location session and an indication of thesecond location session from the network entity, wherein at least one ofthe second indication of the first location session and the indicationof the second location session indicate that the second location sessionis different from the first location session.

In one implementation, a method for supporting location services for auser equipment (UE) performed by a location server includes sending aninitial message for a first location session and a first indication ofthe first location session to a network entity; sending a final messagefor the first location session and a second indication of the firstlocation session to the network entity; and sending an initial messagefor a second location session and an indication of the second locationsession to the network entity, wherein at least one of the secondindication of the first location session and the indication of thesecond location session indicate that the second location session isdifferent from the first location session.

In one implementation, a location server for supporting locationservices for a user equipment (UE) includes an external interfaceconfigured to communicate with a wireless network; memory configured tostore instructions; and at least one processor coupled to the externalinterface and the memory, the at least one processor configured by theinstructions stored in the memory to: send via the external interface aninitial message for a first location session and a first indication ofthe first location session to a network entity; send via the externalinterface a final message for the first location session and a secondindication of the first location session to the network entity; and sendvia the external interface an initial message for a second locationsession and an indication of the second location session to the networkentity, wherein at least one of the second indication of the firstlocation session and the indication of the second location sessionindicate that the second location session is different from the firstlocation session.

In one implementation, a location server for supporting locationservices for a user equipment (UE), the location server includes meansfor sending an initial message for a first location session and a firstindication of the first location session to a network entity; means forsending a final message for the first location session and a secondindication of the first location session to the network entity; andmeans for sending an initial message for a second location session andan indication of the second location session to the network entity,wherein at least one of the second indication of the first locationsession and the indication of the second location session indicate thatthe second location session is different from the first locationsession.

In one implementation, a non-transitory storage medium including programcode stored thereon, the program code is operable to configure at leastone processor in a location server for supporting location services fora user equipment (UE), includes program code to send an initial messagefor a first location session and a first indication of the firstlocation session to a network entity; program code to send a finalmessage for the first location session and a second indication of thefirst location session to the network entity; and program code to sendan initial message for a second location session and an indication ofthe second location session to the network entity, wherein at least oneof the second indication of the first location session and theindication of the second location session indicate that the secondlocation session is different from the first location session.

In one implementation, a method for supporting location services for auser equipment (UE) performed by a network entity includes receiving aninitial message for a first location session for the UE and a firstindication of the first location session from a location server; sendingthe initial message for the first location session and the firstindication of the first location session to the UE; receiving a finalmessage for the first location session and a second indication of thefirst location session from the location server; sending the finalmessage for the first location session and the second indication of thefirst location session to the UE; receiving an initial message for asecond location session for the UE and an indication of the secondlocation session from the location server; and sending the initialmessage for the second location session and the indication of the secondlocation session to the UE, wherein at least one of the secondindication of the first location session and the indication of thesecond location session indicate that the second location session isdifferent from the first location session.

In one implementation, a network entity for supporting location servicesfor a user equipment (UE) performed by the network entity includes anexternal interface configured to communicate with a wireless network;memory configured to store instructions; and at least one processorcoupled to the external interface and the memory, the at least oneprocessor configured by the instructions stored in the memory to:receive via the external interface an initial message for a firstlocation session for the UE and a first indication of the first locationsession from a location server; send via the external interface theinitial message for the first location session and the first indicationof the first location session to the UE; receive via the externalinterface a final message for the first location session and a secondindication of the first location session from the location server; sendvia the external interface the final message for the first locationsession and the second indication of the first location session to theUE; receive via the external interface an initial message for a secondlocation session for the UE and an indication of the second locationsession from the location server; and send via the external interfacethe initial message for the second location session and the indicationof the second location session to the UE, wherein at least one of thesecond indication of the first location session and the indication ofthe second location session indicate that the second location session isdifferent from the first location session.

In one implementation, a network entity for supporting location servicesfor a user equipment (UE) performed by the network entity, the networkentity includes means for receiving an initial message for a firstlocation session for the UE and a first indication of the first locationsession from a location server; means for sending the initial messagefor the first location session and the first indication of the firstlocation session to the UE; means for receiving a final message for thefirst location session and a second indication of the first locationsession from the location server; means for sending the final messagefor the first location session and the second indication of the firstlocation session to the UE; means for receiving an initial message for asecond location session for the UE and an indication of the secondlocation session from the location server; and means for sending theinitial message for the second location session and the indication ofthe second location session to the UE, wherein at least one of thesecond indication of the first location session and the indication ofthe second location session indicate that the second location session isdifferent from the first location session.

In one implementation, a non-transitory storage medium including programcode stored thereon, the program code is operable to configure at leastone processor in a network entity for supporting location services for auser equipment (UE), includes program code to receive an initial messagefor a first location session for the UE and a first indication of thefirst location session from a location server; program code to send theinitial message for the first location session and the first indicationof the first location session to the UE; program code to receive a finalmessage for the first location session and a second indication of thefirst location session from the location server; program code to sendthe final message for the first location session and the secondindication of the first location session to the UE; program code toreceive an initial message for a second location session for the UE andan indication of the second location session from the location server;and program code to send the initial message for the second locationsession and the indication of the second location session to the UE,wherein at least one of the second indication of the first locationsession and the indication of the second location session indicate thatthe second location session is different from the first locationsession.

BRIEF DESCRIPTION OF THE DRAWINGS

An understanding of the nature and advantages of various embodiments maybe realized by reference to the following figures.

FIG. 1 is a simplified block diagram illustrating a communication systemfor roaming support of UE location using an Evolved Packet System (EPS).

FIG. 2 is a simplified block diagram illustrating a communication systemfor non-roaming support of UE location using a 5G Core network (5GCN).

FIG. 3 is a simplified block diagram illustrating a communication systemfor roaming support of UE location using a 5GCN.

FIG. 4 shows a signaling flow illustrating various enhancements to anLPP protocol to indicate when one location session is different fromanother location session.

FIG. 5 shows a signaling flow illustrating use of correlation ID as anenhancement to the LPP protocol to indicate when one location session isdifferent from another location session.

FIG. 6 shows a process flow illustrating a method for supportinglocation services for a user equipment (UE) performed by a locationserver in which enhancements to a positioning protocol are used toindicate when one location session is different from another locationsession.

FIG. 7 shows a process flow illustrating a method for supportinglocation services for a user equipment (UE) performed by the UE in whichenhancements to a positioning protocol are used to indicate when onelocation session is different from another location session.

FIG. 8 shows a process flow illustrating a method for supportinglocation services for a user equipment (UE) performed by a networkentity in which enhancements to a positioning protocol are used toindicate when one location session is different from another locationsession.

FIG. 9 is a block diagram of an embodiment of a location server capableof using enhancements to a positioning protocol to indicate when onelocation session is different from another location session.

FIG. 10 is a block diagram of an embodiment of a UE capable of usingenhancements to a positioning protocol to determine when one locationsession is different from another location session.

FIG. 11 is a block diagram of an embodiment of a network entity capableof using enhancements to a positioning protocol to indicate when onelocation session is different from another location session.

Like reference numbers and symbols in the various figures indicate likeelements, in accordance with certain example implementations. Inaddition, multiple instances of an element may be indicated by followinga first number for the element with a letter or with a hyphen and asecond number. For example, multiple instances of an element 110 may beindicated as 110-1, 110-2, 110-3 etc. When referring to such an elementusing only the first number, any instance of the element is to beunderstood (e.g. element 110 in the previous example would refer toelements 110-1, 110-2 and 110-3).

DETAILED DESCRIPTION

References throughout this specification to one implementation, animplementation, one embodiment, an embodiment, and/or the like mean thata particular feature, structure, characteristic, and/or the likedescribed in relation to a particular implementation and/or embodimentis included in at least one implementation and/or embodiment of claimedsubject matter. Thus, appearances of such phrases, for example, invarious places throughout this specification are not necessarilyintended to refer to the same implementation and/or embodiment or to anyone particular implementation and/or embodiment. Furthermore, it is tobe understood that particular features, structures, characteristics,and/or the like described are capable of being combined in various waysin one or more implementations and/or embodiments and, therefore, arewithin intended claim scope. However, these and other issues have apotential to vary in a particular context of usage. In other words,throughout the disclosure, particular context of description and/orusage provides helpful guidance regarding reasonable inferences to bedrawn; however, likewise, “in this context” in general without furtherqualification refers to the context of the present disclosure.

To support positioning of a mobile device, two broad classes of locationsolution have been defined: control plane and user plane. With controlplane (CP) location, signaling related to positioning and support ofpositioning may be carried over existing network (and mobile device)signaling interfaces and using existing protocols dedicated to thetransfer of signaling. With user plane (UP) location, signaling relatedto positioning and support of positioning may be carried as part ofother data using such protocols as the Internet Protocol (IP),Transmission Control Protocol (TCP) and User Datagram Protocol (UDP).

The Third Generation Partnership Project (3GPP) has defined controlplane location solutions for mobile devices that use radio accessaccording to Global System for Mobile communications GSM (2G), UniversalMobile Telecommunications System (UMTS) (3G), Long Term Evolution (LTE)(4G) and New Radio (NR) (5G). These solutions are defined in 3GPP TSs23.271 and 23.273 (common parts), 43.059 (GSM access), 25.305 (UMTSaccess), 36.305 (LTE access) and 38.305 (NR access). The Open MobileAlliance (OMA) has similarly defined a UP location solution known asSecure User Plane Location (SUPL) which can be used to locate a mobiledevice accessing any of a number of radio interfaces that support IPpacket access such as General Packet Radio Service (GPRS) with GSM, GPRSwith UMTS, or IP access with LTE or NR.

Both CP and UP location solutions may employ a location server (LS) tosupport positioning. The LS may be part of or accessible from a servingnetwork or a home network for a UE or may simply be accessible over theInternet or over a local Intranet. If positioning of a UE is needed, anLS may instigate a session (e.g. a location session or a SUPL session)with the UE, coordinate location measurements by the UE and/or bynetwork entities and enable determination of an estimated location ofthe UE. During a location session, an LS may request positioningcapabilities of the UE (or the UE may provide them without a request),may provide assistance data to the UE (e.g. if requested by the UE or inthe absence of a request) and may request a location estimate orlocation measurements from the UE, e.g. for the GNSS, OTDOA and/orEnhanced Cell ID (ECID) position methods. Assistance data may enable aUE to acquire and measure radio signals (e.g. GNSS and/or PRS signals),e.g. by providing expected characteristics of these signals such asfrequency, expected time of arrival, signal coding, signal Doppler.

In a UE based mode of operation, assistance data may also or instead beused by a UE to help determine a location estimate from the resultinglocation measurements (e.g., if the assistance data provides satelliteephemeris data in the case of GNSS positioning or base station locationsand other base station characteristics such as PRS timing in the case ofterrestrial positioning using OTDOA).

In an alternative UE assisted mode of operation, a UE may returnlocation measurements to an LS which may determine an estimated locationof the UE based on these measurements and possibly based also on otherknown or configured data (e.g. satellite ephemeris data for GNSSlocation or base station characteristics including base stationlocations and possibly PRS timing in the case of terrestrial positioningusing OTDOA).

In another standalone mode of operation, a UE may make location relatedmeasurements without any positioning assistance data from an LS and mayfurther compute a location or a change in location without anypositioning assistance data from an LS. Position methods that may beused in a standalone mode include GPS and GNSS (e.g. if a UE obtainssatellite orbital data from data broadcast by GPS and GNSS satellitesthemselves) as well as sensors. It is noted that the terms “positioningassistance data”, “location assistance data” and “assistance data” (AD)are used synonymously herein to refer to data which may be provided to amobile device via broadcast or by point to point means to assist themobile device to obtain location measurements (also referred to aspositioning measurements) and/or to compute a location estimate frompositioning measurements.

In the case of 3GPP CP location, an LS may be an enhanced serving mobilelocation center (E-SMLC) in the case of LTE access, a standalone SMLC(SAS) in the case of UMTS access, a serving mobile location center(SMLC) in the case of GSM access, or a Location Management Function(LMF) in the case of 5G NR access. In the case of OMA SUPL location, anLS may be a SUPL Location Platform (SLP) which may act as any of: (i) ahome SLP (H-SLP) if in or associated with the home network of a UE or ifproviding a permanent subscription to a UE for location services; (ii) adiscovered SLP (D-SLP) if in or associated with some other (non-home)network or if not associated with any network; (iii) an Emergency SLP(E-SLP) if supporting location for an emergency call instigated by theUE; or (iv) a visited SLP (V-SLP) if in or associated with a servingnetwork or a current local area for a UE.

During a location session, an LS and UE may exchange messages definedaccording to some positioning protocol in order to coordinate thedetermination of an estimated location. Possible positioning protocolsmay include, for example, the LTE Positioning Protocol (LPP) defined by3GPP in 3GPP TS 36.355 and the LPP Extensions (LPPe) protocol defined byOMA in OMA TSs OMA-TS-LPPe-V1_0, OMA-TS-LPPe-V1_1 and OMA-TS-LPPe-V2_0.The LPP and LPPe protocols may be used in combination where an LPPmessage contains one embedded LPPe message. The combined LPP and LPPeprotocols may be referred to as LPP/LPPe. LPP and LPP/LPPe may be usedto help support the 3GPP control plane solution for LTE access, in whichcase LPP or LPP/LPPe messages are exchanged between a UE and E-SMLC. LPPor LPP/LPPe messages may be exchanged between a UE and E-SMLC via aserving Mobility Management Entity (MME) and a serving eNodeB for theUE. LPP and LPP/LPPe may also be used to help support the OMA SUPLsolution for many types of wireless access that support IP messaging(such as LTE, NR and WiFi), where LPP or LPP/LPPe messages are exchangedbetween a SUPL Enabled Terminal (SET), which is the term used for a UEwith SUPL, and an SLP, and may be transported within SUPL messages suchas a SUPL POS or SUPL POS INIT message. It is noted that while the LPPpositioning protocol is discussed in the below description andillustrations in FIGS. 4-11, it should be understood that thedescription and illustrations are not limited to one particularpositioning protocol, such as LPP.

An LS and a base station (e.g. an eNodeB for LTE access) may exchangemessages to enable the LS to (i) obtain position measurements for aparticular UE from the base station, or (ii) obtain location informationfrom the base station not related to a particular UE such as thelocation coordinates of an antenna for the base station, the cells (e.g.cell identities) supported by the base station, cell timing for the basestation and/or parameters for signals transmitted by the base stationsuch as PRS signals. In the case of LTE access, the LPP A (LPPa)protocol defined in 3GPP TS 36.455 may be used to transfer such messagesbetween a base station that is an eNodeB and an LS that is an E-SMLC.

During a location session between a UE and an LS where LPP is used, theUE may receive multiple requests (conveyed in LPP messages) for locationinformation (e.g. location measurements) for different position methods.For example, LPP or LPP/LPPe request messages for location informationmay be received for position methods, such as Global NavigationSatellite System (GNSS), Observed Time Difference of Arrival (OTDOA),enhanced Cell ID (ECID), LPPe position methods, Wireless Local AreaNetwork (WLAN) positioning, uncompensated barometric pressure (UBP)(Baro Sensor) and Bluetooth-Low Energy (BTLE). A number of these requestlocation information messages may arrive as independent messages withinthe same location session or as part of different location sessions. Asa result, it may not always be possible for a UE to determine when aNetwork Initiated location session has ended. The inability to clearlydefine the end of a location session may be the source of errors. Forexample, some UEs may not have an ability to support more than onelocation session at a time, which may cause the UE to ignore or reject areceived LPP message for a new LPP session when a previous LPP sessionhas ended but is perceived by the UE to be still continuing. In anotherexample, a UE may receive LPP messages for different LPP sessions butmay erroneously treat all LPP messages as being part of the same LPPsession which may cause memory problems for the UE in terms of storinginformation for all received LPP messages as part of one sessionEnhancements to a positioning protocol, such as including a sessionindication in one or more messages, as described below, may be used toindicate when one location session is different from another locationsession.

FIG. 1 is a diagram illustrating a communication system 100 for locationsupport of a user equipment (UE) 105 that supports and is currentlyusing Long Term Evolution (LTE) radio access (also referred to aswideband LTE) or Narrow Band Internet of Things (NB-IoT) radio access(also referred to as narrowband LTE), where NB-IoT and LTE may be asdefined by 3GPP—e.g. in 3GPP TS 36.300. The communication system 100 maybe referred to as an Evolved Packet System (EPS). As illustrated, thecommunication system 100 may include the UE 105, an Evolved UniversalMobile Telecommunications Service (UMTS) Terrestrial Radio Access(E-UTRA) Network (E-UTRAN) 120, and an Evolved Packet Core (EPC) 130.The E-UTRAN 120 and the EPC 130 may be part of a Visited Public LandMobile Network (VPLMN) that is a serving network for the UE 105 andcommunicates with a Home Public Land Mobile Network (HPLMN) 140 for theUE 105. The VPLMN E-UTRAN 120, VPLMN EPC 130 and/or HPLMN 140 mayinterconnect with other networks. For example, the Internet may be usedto carry messages to and from different networks such as the HPLMN 140and the VPLMN EPC 130. For simplicity these networks and associatedentities and interfaces are not shown. As shown, the communicationsystem 100 provides packet-switched services to the UE 105. However, asthose skilled in the art will readily appreciate, the various conceptspresented throughout this disclosure may be extended to networksproviding circuit-switched services.

The UE 105 may comprise any electronic device configured for NB-IoTand/or LTE radio access, for example. The UE 105 may be referred to as adevice, a wireless device, a mobile terminal, a terminal, a mobilestation (MS), a mobile device, a SET, or by some other name and maycorrespond to (or be part of) a smart watch, digital glasses, fitnessmonitor, smart car, smart appliance, cellphone, smartphone, laptop,tablet, PDA, tracking device, control device, or some other portable ormoveable device. A UE 105 may comprise a single entity or may comprisemultiple entities such as in a personal area network where a user mayemploy audio, video and/or data I/O devices and/or body sensors and aseparate wireline or wireless modem. Typically, though not necessarily,a UE 105 may support wireless communication with one or more types ofWireless Wide Area Network (WWAN) such as a WWAN supporting GlobalSystem for Mobile Communications (GSM), Code Division Multiple Access(CDMA), Wideband CDMA (WCDMA), Long Term Evolution (LTE), Narrow BandInternet of Things (NB-IoT), Enhanced Machine Type Communications (eMTC)also referred to as LTE category M1 (LTE-M), High Rate Packet Data(HRPD), 5G NR, WiMax, etc. VPLMN EPC 130 combined with VPLMN E-UTRAN120, and HPLMN 140, may be examples of a WWAN. A UE 105 may also supportwireless communication with one or more types of Wireless Local AreaNetwork (WLAN) such as a WLAN supporting IEEE 802.11 WiFi or Bluetooth®(BT). UE 105 may also support communication with one or more types ofwireline network such as by using a Digital Subscriber Line (DSL) orpacket cable for example. Although FIG. 1 shows only one UE 105, theremay be many other UEs that can each correspond to UE 105.

The UE 105 may enter a connected state with a wireless communicationnetwork that may include the E-UTRAN 120. In one example, UE 105 maycommunicate with a cellular communication network by transmittingwireless signals to, and/or receiving wireless signals from, a cellulartransceiver, such as an evolved Node B (eNodeB or eNB) 104 in theE-UTRAN 120. The E-UTRAN 120 may include one or more additional eNBs106. The eNB 104 provides user plane and control plane protocolterminations toward the UE 105. The eNB 104 may comprise a serving eNBfor UE 105 and may also be referred to as a base station, a basetransceiver station, a radio base station, a radio transceiver, a radionetwork controller, a transceiver function, a base station subsystem(BSS), an extended service set (ESS), or by some other suitableterminology. The UE 105 also may transmit wireless signals to, orreceive wireless signals from, a local transceiver (not shown in FIG.1), such as an access point (AP), femtocell, Home Base Station, smallcell base station, Home Node B (HNB) or Home eNodeB (HeNB), which mayprovide access to a wireless local area network (WLAN, e.g., IEEE 802.11network), a wireless personal area network (WPAN, e.g., Bluetoothnetwork) or a cellular network (e.g. an LTE network or other wirelesswide area network such as those discussed in the next paragraph). Ofcourse, it should be understood that these are merely examples ofnetworks that may communicate with a mobile device over a wireless link,and claimed subject matter is not limited in this respect.

Examples of network technologies that may support wireless communicationinclude NB-IoT and LTE, but may further include GSM, CDMA, WCDMA, HRPD,eMTC and NR. NB-IoT, GSM, WCDMA, LTE, eMTC and NR are technologiesdefined by 3GPP. CDMA and HRPD are technologies defined by the 3rdGeneration Partnership Project 2 (3GPP2). Cellular transceivers, such aseNBs 104 and 106, may comprise deployments of equipment providingsubscriber access to a wireless telecommunication network for a service(e.g., under a service contract). Here, a cellular transceiver mayperform functions of a cellular base station in servicing subscriberdevices within a cell determined based, at least in part, on a range atwhich the cellular transceiver is capable of providing access service.

The eNBs 104 and 106 may be connected by an interface (e.g. the 3GPP S1interface) to the VPLMN EPC 130. The EPC 130 includes a MobilityManagement Entity (MME) 134, and a Serving Gateway (SGW) 136 throughwhich data (e.g. Internet Protocol (IP) packets) to and from the UE 105may be transferred. The MME 134 may be the serving MME for UE 105 and isthen the control node that processes the signaling between the UE 105and the EPC 130 and supports attachment and network connection of UE105, mobility of UE 105 (e.g. via handover between network cells) aswell as establishing and releasing data bearers on behalf of the UE 105.Generally, the MME 134 provides bearer and connection management for theUE 105 and may be connected to the SGW 136, the eNBs 104 and 106, anEnhanced Serving Mobile Location Center (E-SMLC) 132 and a VisitedGateway Mobile Location Center (V-GMLC) 116 in the VPLMN EPC 130.

The E-SMLC 132 may support location of the UE 105 using the 3GPP controlplane (CP) location solution defined in 3GPP technical specifications(TSs) 23.271 and 36.305. The V-GMLC 116, which may also be referred tosimply as a Gateway Mobile Location Center (GMLC) 116, may provideaccess on behalf of an external client (e.g. external client 150) oranother network (e.g. HPLMN 140) to the location of UE 105. The externalclient 150 may comprise a web server or remote application that may havesome association with UE 105 (e.g. may be accessed by a user of UE 105via VPLMN E-UTRAN 120, VPLMN EPC 130 and HPLMN 140) or may be a server,application or computer system providing a location service to someother user or users which may include obtaining and providing thelocation of UE 105 (e.g. to enable a service such as friend or relativefinder, asset tracking or child or pet location).

E-SMLC 132 may be connected to or have access to one or more referencestations 171 which may be part of VPLMN EPC 130 or separate from VPLMNEPC 130 (e.g. part of a GNSS reference network and owned and operated bya service provider different to the operator of VPLMN EPC 130). Areference station 171 may comprise or include a GNSS receiver configuredto acquire, measure, and decode signals transmitted by one or moreGNSSs. A reference station 171 may be configured to obtain or determineorbital and timing data for Satellite Vehicles (SVs) 190 for one or moreGNSSs and infer information for environmental factors that can affectGNSS location such as ionospheric and tropospheric delay. A referencestation 171 may transfer determined information to E-SMLC 132—e.g.periodically or whenever the determined information changes.

As illustrated, the HPLMN 140 includes a Home Gateway Mobile LocationCenter (H-GMLC) 148 that may be connected to the V-GMLC 116 (e.g. viathe Internet), as well as a Packet Data Network Gateway (PDG) 144 thatmay be connected to the SGW 136 (e.g. via the Internet). The PDG 144 mayprovide UE 105 with Internet Protocol (IP) address allocation and IP andother data access to external networks (e.g. the Internet) and toexternal clients (e.g. external client 150) and external servers, aswell as other data transfer related functions. In some cases, PDG 144may be located in VPLMN EPC 130 and not in HPLMN 140 when the UE 105receives local IP breakout. The PDG 144 may be connected to a locationserver, such as H-SLP 142. The H-SLP 142 may support the SUPL UPlocation solution defined by OMA and may support location services forUE 105 based on subscription information for UE 105 stored in H-SLP 142.In some embodiments of communication system 100, a Discovered SLP(D-SLP) or Emergency SLP (E-SLP) (not shown in FIG. 1), in or accessiblefrom VPLMN EPC 130, may be used to locate UE 105 using the SUPL UPsolution.

The H-GMLC 148 may be connected to a Home Subscriber Server (HSS) 145for UE 105, which is a central database that contains user-related andsubscription-related information for UE 105. The H-GMLC 148 may providelocation access to the UE 105 on behalf of external clients such asexternal client 150. One or more of the H-GMLC 148, PDG 144, and H-SLP142 may be connected to the external client 150, e.g., through anothernetwork, such as the Internet. In some cases, a Requesting GMLC (R-GMLC)located in another PLMN (not shown in FIG. 1) may be connected to H-GMLC148 (e.g. via the Internet) in order to provide location access to UE105 on behalf of external clients connected to the R-GMLC. The R-GMLC,H-GMLC 148 and V-GMLC 116 may support location access to the UE 105using the 3GPP CP solution defined in 3GPP TS 23.271.

It should be understood that while a VPLMN network (comprising VPLMNE-UTRAN 120 and VPLMN EPC 130) and a separate HPLMN 140 are illustratedin FIG. 1; both PLMNs (networks) may be the same PLMN. In that case, (i)the H-SLP 142, PDG 144, and HSS 145, may be in the same network (EPC) asthe MME 134, and (ii) the V-GMLC 116 and the H-GMLC 148 may comprise thesame GMLC.

In particular implementations, the UE 105 may have circuitry andprocessing resources capable of obtaining location related measurements(also referred to as location measurements), such as measurements forsignals received from GPS or other Satellite Positioning System (SPS)SVs 190, measurements for cellular transceivers such as eNBs 104 and106, and/or measurements for local transceivers. UE 105 may further havecircuitry and processing resources capable of computing a position fixor estimated location of UE 105 based on these location relatedmeasurements. In some implementations, location related measurementsobtained by UE 105 may be transferred to a location server, such as theE-SMLC 132, H-SLP 142 or LMF 152 (described later for FIG. 2), afterwhich the location server may estimate or determine a location for UE105 based on the measurements.

Location related measurements obtained by UE 105 may includemeasurements of signals received from SVs 190 that are part of an SPS orGlobal Navigation Satellite System (GNSS) such as the Global PositioningSystem (GPS), GLONASS, Galileo or Beidou and/or may include measurementsof signals received from terrestrial transmitters fixed at knownlocations (e.g., such as eNB 104, eNB 106 or other local transceivers).UE 105 or a separate location server (e.g. E-SMLC 132, H-SLP 142 or LMF152) may then obtain a location estimate for the UE 105 based on theselocation related measurements using any one of several position methodssuch as, for example, GNSS, Assisted GNSS (A-GNSS), Advanced ForwardLink Trilateration (AFLT), Observed Time Difference Of Arrival (OTDOA),Enhanced Cell ID (ECID), WiFi, or combinations thereof. In some of thesetechniques (e.g. A-GNSS, AFLT and OTDOA), pseudoranges or timingdifferences may be measured by UE 105 relative to three or moreterrestrial transmitters fixed at known locations or relative to four ormore SVs with accurately known orbital data, or combinations thereof,based at least in part, on pilot signals, positioning reference signals(PRS) or other positioning related signals transmitted by thetransmitters or SVs and received at the UE 105. Here, location servers,such as E-SMLC 132, H-SLP 142 or LMF 152, may be capable of providingpositioning assistance data to UE 105 including, for example,information regarding signals to be measured by UE 105 (e.g., expectedsignal timing, signal coding, signal frequencies, signal Doppler),locations and/or identities of terrestrial transmitters, and/or signal,timing and orbital information for GNSS SVs 190 to facilitatepositioning techniques such as A-GNSS, AFLT, OTDOA and ECID. Thefacilitation may include improving signal acquisition and measurementaccuracy by UE 105 and/or, in some cases, enabling UE 105 to compute itsestimated location based on the location measurements. For example, alocation server may comprise an almanac (e.g., a Base Station Almanac(BSA)) which indicates the locations and identities of cellulartransceivers and transmitters (e.g. eNBs 104 and 106) and/or localtransceivers and transmitters in a particular region or regions such asa particular venue, and may further contain information descriptive ofsignals transmitted by these transceivers and transmitters such assignal power, signal timing, signal bandwidth, signal coding and/orsignal frequency. In the case of ECID, a UE 105 may obtain measurementsof signal strength (e.g. received signal strength indication (RSSI) orreference signal received power (RSRP)) for signals received fromcellular transceivers (e.g., eNBs 104, 106) and/or local transceiversand/or may obtain a signal to noise ratio (S/N), a reference signalreceived quality (RSRQ), or a round trip signal propagation time (RTT)between UE 105 and a cellular transceiver (e.g., eNB 104 or 106) or alocal transceiver. A UE 105 may transfer these measurements to alocation server, such as E-SMLC 132, H-SLP 142 or LMF 152, to determinea location for UE 105, or in some implementations, UE 105 may use thesemeasurements together with positioning assistance data (e.g. terrestrialalmanac data or GNSS SV data such as GNSS Almanac and/or GNSS Ephemerisinformation) received from the location server to determine a locationfor UE 105.

In the case of OTDOA, UE 105 may measure a Reference Signal TimeDifference (RSTD) between signals, such as a Position Reference Signal(PRS) or Cell Specific Reference Signal (CRS), received from nearbytransceivers or base stations (e.g. eNBs 104 and 106). An RSTDmeasurement may provide the time of arrival difference between signals(e.g. CRS or PRS) received at UE 105 from two different transceivers(e.g. an RSTD between signals received from eNB 104 and from eNB 106).The UE 105 may return the measured RSTDs to a location server (e.g.E-SMLC 132, H-SLP 142 or LMF 152) which may compute an estimatedlocation for UE 105 based on known locations and known signal timing forthe measured transceivers. In some implementations of OTDOA, the signalsused for RSTD measurements (e.g. PRS or CRS signals) may be accuratelysynchronized by the transceivers or transmitters to a common universaltime such as GPS time or coordinated universal time (UTC), e.g., using aGPS receiver at each transceiver or transmitter to accurately obtain thecommon universal time.

An estimate of a location of a UE 105 may be referred to as a location,location estimate, location fix, fix, position, position estimate orposition fix, and may be geodetic, thereby providing locationcoordinates for the UE 105 (e.g., latitude and longitude) which may ormay not include an altitude component (e.g., height above sea level,height above or depth below ground level, floor level or basementlevel). Alternatively, a location of the UE 105 may be expressed as acivic location (e.g., as a postal address or the designation of somepoint or small area in a building such as a particular room or floor). Alocation of a UE 105 may also include an uncertainty and may then beexpressed as an area or volume (defined either geodetically or in civicform) within which the UE 105 is expected to be located with some givenor default probability or confidence level (e.g., 67% or 95%). Alocation of a UE 105 may further be an absolute location (e.g. definedin terms of a latitude, longitude and possibly altitude and/oruncertainty) or may be a relative location comprising, for example, adistance and direction or relative X, Y (and Z) coordinates definedrelative to some origin at a known absolute location, which may bedefined geographically, in civic terms, or by reference to a point,area, or volume indicated on a map, floor plan or building plan. In thedescription contained herein, the use of the term location may compriseany of these variants unless indicated otherwise. When computing thelocation of a UE, it is common to solve for local x, y, and possibly zcoordinates and then, if needed, convert the local coordinates intoabsolute ones (e.g. for latitude, longitude and altitude above or belowmean sea level). Measurements (e.g. obtained by UE 105 or by anotherentity such as eNB 104) that are used to determine (e.g. calculate) alocation estimate for UE 105 may be referred to as measurements,location measurements, location related measurements, positioningmeasurements or position measurements and the act of determining alocation for the UE 105 may be referred to as positioning of the UE 105or locating the UE 105.

FIG. 2 is a simplified block diagram illustrating a communication system200 for non-roaming support of UE location using a 5G CP locationsolution. The non-roaming communication system 200 comprises a UE 105and components of a Fifth Generation (5G) network comprising a NextGeneration Radio Access Network (NG-RAN) 112, which includes basestations (BSs) sometimes referred to as New Radio (NR) NodeBs (alsoreferred to as gNBs) 110-1, 110-2 and 110-3 (collectively andgenerically referred to herein as gNBs 110), and a 5G Core Network(SGCN) 131 that is in communication with an external client 150. A 5Gnetwork may also be referred to as a New Radio (NR) network; NG-RAN 112may be referred to as an NR RAN or a 5G RAN; and SGCN 131 may bereferred to as an Next Generation (NG) Core network (NGC). Thecommunication system 200 may further utilize information from spacevehicles (SVs) 190 for a Global Navigation Satellite System (GNSS) likeGPS, GLONASS, Galileo or Beidou or some other local or regionalSatellite Positioning System (SPS) such as IRNSS, EGNOS or WAAS.Additional components of the communication system 200 are describedbelow. The communication system 200 may include additional oralternative components.

It should be noted that FIG. 2 provides only a generalized illustrationof various components, any or all of which may be utilized asappropriate, and each of which may be duplicated or omitted asnecessary. Specifically, although only one UE 105 is illustrated, itwill be understood that many UEs (e.g., hundreds, thousands, millions,etc.) may utilize the communication system 200. Similarly, thecommunication system 200 may include a larger or smaller number of SVs190, gNBs 110, external clients 150, and/or other components. Theillustrated connections that connect the various components in thecommunication system 200 include data and signaling connections whichmay include additional (intermediary) components, direct or indirectphysical and/or wireless connections, and/or additional networks.Furthermore, components may be rearranged, combined, separated,substituted, and/or omitted, depending on desired functionality.

While FIG. 2 illustrates a 5G-based network, similar networkimplementations and configurations may be used for other communicationtechnologies, such as 3G, Long Term Evolution (LTE), and IEEE 802.11WiFi etc. For example, where a Wireless Local Area Network (WLAN), e.g.,IEEE 802.11 radio interface, is used, the UE 105 may communicate with anAccess Network (AN), as opposed to an NG-RAN, and accordingly, component112 is sometimes referred to herein as an AN or as a RAN, denoted by theterm “(R)AN” or “(R)AN 112”. In the case of an AN (e.g. IEEE 802.11 AN),the AN may be connected to a Non-3GPP Interworking Function (N3IWF)(e.g. in 5GCN 131) (not shown in FIG. 2), with the N3IWF connected toAMF 154.

A location server, such as the LMF 152, may be capable of providingpositioning assistance data to UE 105 including, for example,information regarding signals to be measured (e.g., expected signaltiming, signal coding, signal frequencies, signal Doppler), locationsand identities of terrestrial transmitters (e.g. gNBs 110) and/orsignal, timing and orbital information for GNSS SVs 190 to facilitatepositioning techniques such as A-GNSS, AFLT, OTDOA and ECID. Thefacilitation may include improving signal acquisition and measurementaccuracy by UE 105 and, in some cases, enabling UE 105 to compute itsestimated location based on the location measurements. For example, alocation server (e.g. LMF 152) may comprise an almanac which indicateslocations and identities of cellular transceivers and/or localtransceivers in a particular region or regions such as a particularvenue, and may provide information descriptive of signals transmitted bya cellular base station or AP (e.g. a gNB 110) such as transmissionpower and signal timing. A UE 105 may obtain measurements of signalstrengths (e.g. received signal strength indication (RSSI)) for signalsreceived from cellular transceivers and/or local transceivers and/or mayobtain a signal to noise ratio (S/N), a reference signal received power(RSRP), a reference signal received quality (RSRQ), a time of arrival(TOA), or a round trip signal propagation time (RTT) between UE 105 anda cellular transceiver (e.g. a gNB 110) or a local transceiver (e.g. aWiFi access point (AP)). A UE 105 may transfer these measurements to alocation server, such as LMF 152, to determine a location for UE 105, orin some implementations, may use these measurements together withassistance data (e.g. terrestrial almanac data or GNSS satellite datasuch as GNSS Almanac and/or GNSS ephemeris information) received from alocation server (e.g. LMF 152) or broadcast by a base station (e.g. agNB 110) in NG-RAN 112 to determine a location for UE 105.

The UE 105 may measure one or more of a Reference Signal Time Difference(RSTD), a Receive-Transmit (Rx-Tx) time difference, an Angle of Arrival(AOA), a Round Trip signal propagation Time (RTT), an Angle of Departure(ADD), a Reference Signal Strength Indication (RSSI), a Reference SignalReceived Power (RSRP), a Reference Signal Received Quality (RSRQ). Inthe case of OTDOA, UE 105 may measure a Reference Signal Time Difference(RSTD) between signals such as a position reference signal (PRS), Cellspecific Reference Signal (CRS), or Tracking Reference Signal (TRS)transmitted by nearby pairs of transceivers and base stations (e.g. gNBs110). An RSTD measurement may provide the time of arrival differencebetween signals (e.g. TRS, CRS or PRS) received at UE 105 from twodifferent transceivers. The UE 105 may return the measured RSTDs to alocation server (e.g. LMF 152) which may compute an estimated locationfor UE 105 based on known locations and known signal timing for themeasured transceivers. In some implementations of OTDOA, the signalsused for RSTD measurements (e.g. PRS or CRS signals) may be accuratelysynchronized by the transceivers to a common universal time such as GPStime or Coordinated Universal Time (UTC), e.g., using a GPS or GNSSreceiver at each transceiver to accurately obtain the common universaltime.

As shown in FIG. 2, pairs of gNBs 110 in NG-RAN 112 may be connected toone another, e.g., directly as shown in FIG. 2 or indirectly via othergNBs 110. Access to the 5G network is provided to UE 105 via wirelesscommunication between the UE 105 and one or more of the gNBs 110, whichmay provide wireless communication access to the 5GCN 131 on behalf ofthe UE 105 using 5G NR. In FIG. 2, the serving gNB for UE 105 is assumedto be gNB 110-1, although other gNBs (e.g. gNB 110-2 and/or gNB 110-3)may act as a serving gNB if UE 105 moves to another location or may actas a secondary gNB to provide additional throughout and bandwidth to UE105. Some gNBs 110 in FIG. 2 (e.g. gNB 110-2 or gNB 110-3) may beconfigured to function as positioning-only beacons which may transmitsignals (e.g. directional PRS) to assist positioning of UE 105 but maynot receive signals from UE 105 or from other UEs.

As noted, while FIG. 2 depicts nodes configured to communicate accordingto 5G communication protocols, nodes configured to communicate accordingto other communication protocols, such as, for example, LTE protocols,may be used. Such nodes, configured to communicate using differentprotocols, may be controlled, at least in part, by the 5GCN 131. Thus,the NG-RAN 112 may include any combination of gNBs, evolved NodeBs(eNBs), or other types of base stations or access points. As an example,NG-RAN 112 may include one or more next generation eNBs (ng-eNBs) 114which provide LTE wireless access to UE 105 and may connect to entitiesin 5GCN 131 such as AMF 154.

The gNBs 110 and/or the ng-eNB 114 can communicate with the Access andMobility Management Function (AMF) 154, which, for positioningfunctionality, communicates with a Location Management Function (LMF)152. The AMF 154 may support mobility of the UE 105, including cellchange and handover and may participate in supporting a signalingconnection to the UE 105 and possibly helping establish and releaseProtocol Data Unit (PDU) sessions for UE 105. Other functions of AMF 154may include: termination of a control plane (CP) interface from NG-RAN112; termination of Non-Access Stratum (NAS) signaling connections fromUEs such as UE 105; NAS ciphering and integrity protection; registrationmanagement; connection management; reachability management; mobilitymanagement; access authentication and authorization.

The LMF 152 may support positioning of the UE 105 when UE 105 accessesthe NG-RAN 112 and may support position procedures/methods such asAssisted GNSS (A-GNSS), Observed Time Difference of Arrival (OTDOA),Real Time Kinematic (RTK), Precise Point Positioning (PPP), DifferentialGNSS (DGNSS), Enhanced Cell ID (ECID), angle of arrival (AOA), angle ofdeparture (AOD), WLAN positioning, and/or other position methods. TheLMF 152 may also process location service requests for the UE 105, e.g.,received from the GMLC 155 or from the AMF 154. In some embodiments, anode/system that implements the LMF 152 may additionally oralternatively implement other types of location-support modules, such asan Enhanced Serving Mobile Location Center (E-SMLC) or a Secure UserPlane Location (SUPL) Location Platform (SLP). It will be noted that insome embodiments, at least part of the positioning functionality(including derivation of UE 105′s location) may be performed at the UE105 (e.g., using signal measurements for signals transmitted by wirelessnodes, and assistance data provided to the UE 105).

The GMLC 155 may support one or more GMLC location methods for obtaininga location of a UE 105. With a GMLC location method, GMLC 155 maysupport a location request for the UE 105 received from an externalclient 150 or from NEF 159 and may forward such a location request tothe LMF 152 via the serving AMF 154 or directly. A location responsefrom the LMF 152 (e.g. containing a location estimate for the UE 105)may be similarly returned to the GMLC 155 via the serving AMF 154 ordirectly, and the GMLC 155 may then return the location response (e.g.,containing the location estimate) to the external client 150 or NEF 159.GMLC 155 may contain subscription information for an external client 150and may authenticate and authorize a location request for UE 105 fromexternal client 150. GMLC 155 may further initiate a location sessionfor UE 105 by sending a location request for UE 105 to AMF 154 (e.g.which then forwards the request to LMF 152) and may include in thelocation request an identity for UE 105 and the type of location beingrequested (e.g. such as a current location or a sequence of periodic ortriggered locations). In contrast to a traditional CP location solutionwhere a GMLC 155 may send a location request for UE 105 to a serving AMFfor UE 105 (e.g. AMF 154), GMLC 155 may only send a location request forUE 105 to an LMF such as LMF 152. This may reduce impacts to AMFs (e.g.AMF 154) and may enable more efficient location of UE 105.

As further illustrated in FIG. 2, the LMF 152 and the gNBs 110 maycommunicate using a New Radio Position Protocol A (which may be referredto as NPPa or NRPPa). NRPPa may be defined in 3GPP TS 38.455 and may bethe same as, similar to, or an extension of, the LTE PositioningProtocol A (LPPa) defined in 3GPP Technical Specification (TS) 36.455,with NRPPa messages being transferred between the gNBs 110 and the LMF152 via the AMF 154. As further illustrated in FIG. 2, LMF 152 and UE105 may communicate using the LTE Positioning Protocol (LPP) defined in3GPP TS 36.355, where LPP messages are transferred inside Non-AccessStratum (NAS) transport messages between the UE 105 and the LMF 152 viathe AMF 154 and a serving gNB 110-1 for UE 105. For example, LPPmessages may be transferred between the LMF 152 and the AMF 154 using atransport protocol (e.g. IP based) or a service based operation (e.g.using the Hypertext Transfer Protocol (HTTP)), and may be transferredbetween the AMF 154 and the UE 105 using a NAS transport protocol. TheLPP protocol may be used to support positioning of UE 105 using UEassisted and/or UE based position methods such as A-GNSS, RTK, WLAN,OTDOA and/or ECID. The NRPPa protocol may be used to support positioningof UE 105 using network based position methods such as ECID (when usedwith measurements obtained by a gNB 110 or received from a gNB 110 fromUE 105) and/or may be used by LMF 152 to obtain location relatedinformation from gNBs 110 such as parameters defining positioningreference signal (PRS) transmission from gNBs 110 for support of OTDOA.

With a UE assisted position method, UE 105 may obtain locationmeasurements (e.g. measurements of RSSI, RTT, RSTD, RSRP and/or RSRQ forgNBs 110, ng-eNB 114 or WLAN APs, or measurements of GNSS pseudorange,code phase and/or carrier phase for SVs 190) and may send themeasurements to a location server (e.g. LMF 152) for computation of alocation estimate for UE 105. With a UE based position method, UE 105may obtain location measurements (e.g. which may be the same as orsimilar to location measurements for a UE assisted position method) andmay compute a location of UE 105 (e.g. with the help of assistance datareceived from a location server such as LMF 152 or broadcast by gNBs110, ng-eNB 114 or other base stations or APs). With a network basedposition method, one or more base stations (e.g. gNBs 110 and/or ng-eNB114) or APs may obtain location measurements (e.g. measurements of RSSI,RTT, RSRP, RSRQ or TOA for signals transmitted by UE 105) and/or mayreceive measurements obtained by UE 105, and may send the measurementsto a location server (e.g. LMF 152) for computation of a locationestimate for UE 105.

Information provided by the gNBs 110 to the LMF 152 using NRPPa mayinclude timing and configuration information for PRS transmission andlocation coordinates of the gNBs 110. The LMF 152 can then provide someor all of this information to the UE 105 as assistance data in an LPPmessage via the NG-RAN 112 and the 5GCN 131.

An LPP message sent from the LMF 152 to the UE 105 may instruct the UE105 to do any of a variety of things, depending on desiredfunctionality. For example, the LPP message could contain an instructionfor the UE 105 to obtain measurements for GNSS (or A-GNSS), WLAN, and/orOTDOA (or some other position method). In the case of OTDOA, the LPPmessage may instruct the UE 105 to obtain one or more measurements (e.g.RSTD measurements) of PRS signals transmitted within particular cellssupported by particular gNBs 110 (or supported by one or more ng-eNBs114 or eNBs). The UE 105 may send the measurements back to the LMF 152in an LPP message (e.g. inside a 5G NAS message) via the serving gNB110-1 and the AMF 154.

In some embodiments, LPP may be augmented by or replaced by an NR or NGpositioning protocol (NPP or NRPP) which supports position methods suchas OTDOA and ECID for NR radio access. For example, an LPP message maycontain an embedded NPP message or may be replaced by an NPP message.

When NG-RAN 112 includes one or more ng-eNBs 114, an ng-eNB 114 maycommunicate with LMF 152 using NRPPa in order to support positioning ofUE 105 (e.g. using a network based position method) and/or may enabletransfer of LPP and/or NPP messages between UE 105 and LMF 152 via theng-eNB 114 and AMF 154. An ng-eNB 114 and/or a gNB 110 in NG-RAN 112 mayalso broadcast positioning assistance data to UEs such as UE 105.

As illustrated, a Unified Data Management (UDM) 156 may be connected tothe AMF 154. The UDM 156 is analogous to a Home Subscriber Server (HSS)for LTE access, and if desired, the UDM 156 may be combined with an HSS.The UDM 156 is a central database that contains user-related andsubscription-related information for UE 105 and may perform thefollowing functions: UE authentication, UE identification, accessauthorization, registration and mobility management, subscriptionmanagement and Short Message Service management. The UDM 156 may beconnected to GMLC 155 (not shown in FIG. 2) and/or to NEF 159.

To support services including location services from external clients150 for Internet of Things (IoT) UEs, a Network Exposure Function (NEF)159 may be included in SGCN 131. The NEF 159 may support secure exposureof capabilities and events concerning SGCN 131 and UE 105 to an externalclient 150, Application Function (AF) 163 or Network Function (NF) 161and may enable secure provision of information from external client 150,AF 163 or NF 161 to 5GCN 131. In the context of location services, NEF159 may function to obtain a current or last known location for a UE105, may obtain an indication of a change in location for a UE 105, oran indication of when a UE 105 becomes available (or reachable). Anexternal client 150 or external AF 163 may access NEF 159 directly ormay access a Services Capability Server (SCS, not shown in FIG. 2),which may access NEF 159 on behalf of external client 150 in order toprovide location information to the external client 150 or AF 163 for UE105 via the SCS. The NEF 159 may be connected to the GMLC 155 to supportlast known location, current location and/or deferred periodic andtriggered location for the UE 105 using a GMLC location method supportedby GMLC 155. NEF 159 may also or instead be connected to the AMF 154 tosupport last known location, current location and/or deferred periodicand triggered location for the UE 105 by sending a subscription requestfor UE 105 location to AMF 154, which may avoid a need to use a GMLC155.

FIG. 3 illustrates a communication system 300 that is similar to thecommunication system 200 shown in FIG. 2, but supports location for aroaming UE 105. In the communication system 300, the core network 5GCN131-1 that is in communication with the UE 105 via the NG-RAN 112 is avisited network, i.e., Visited Public Land Mobile Network (VPLMN), whichis in communication with a home network 5GCN, i.e., Home Public LandMobile Network (HPLMN) 141-1. In communication system 300, the VPLMN5GCN 131-1 includes the Location Management Function (LMF) 152. The LMF152 in communication system 300 may perform the same or almost the samefunctions and operations as LMF 152 in the non-roaming communicationsystem of FIG. 2. The VPLMN 5GCN 131-1 also includes a Visited GatewayMobile Location Center (VGMLC) 155V, which is similar to the GMLC 155 inthe non-roaming communication system of FIG. 2, and is designated as155V to indicate that it is located in the visited network for UE 105.As illustrated in FIG. 3, the VGMLC 155V connects to the AMF 154 and mayconnect to the LMF 152 in the VPLMN 5GCN 131-1.

As illustrated, HPLMN 5GCN 141-1 may include a Home GMLC (HGMLC) 155Hthat may be connected to the VGMLC 155V (e.g., via the Internet). TheHGMLC 155H may be similar to the GMLC 155 in the non-roamingcommunication system of FIG. 2, and is designated as 155H to indicatethat it located in the home network for UE 105. The VGMLC 155V and HGMLC155H may be sometimes collectively and generically referred to herein asGMLC 155. The HGMLC 155H is in communication with the external client150 in the HPLMN 141-1 and optionally with AF 163. The NEF 159 may alsobe in communication with the external client 150 and/or AF 163 and mayoperate as NEF 159 as discussed in FIG. 2. The NEF 159 may providelocation access to UE 105 on behalf of external clients such as externalclient 150 and/or AF 163 as discussed in FIG. 2. One or more of the NEF159 and HGMLC 155H may be connected to external client 150 and/or AF163, e.g., through another network, such as the Internet. In some cases,an NF 161 in HPLMN 141-1 may request the location of UE 105 from NEF 159as discussed in FIG. 2.

The terms location session, session, positioning session, LPP session,LPP location session and LPP positioning session are used synonymouslyherein, During an LPP positioning session, the location server, e.g.,E-SMLC 132 or LMF 152, and the UE 105 exchange a number of LPP messages.LPP message types exchanged during an LPP positioning session, forexample, may include an LPP Request Capabilities, an LPP ProvideCapabilities, an LPP Request Assistance Data, an LPP Provide AssistanceData, an LPP Request Location Information and an LPP Provide LocationInformation. Each LPP message may include an acknowledgment request, anacknowledgement indicator, a transaction identifier (ID), an end oftransaction indicator, and/or a sequence number in a header portion ofthe LPP message. The body of each LPP message, which may be empty, ormay contain information specific to a particular LPP message type. Eachtype of LPP message may contain information specific to one or morepositioning methods and/or information common to all positioningmethods, such as Assisted Global Navigation Satellite System (A-GNSS),Observed Time Difference of Arrival (OTDOA), enhanced Cell ID (ECID),LPPe position methods, Wireless Local Area Network (WLAN) positioning,uncompensated barometric pressure (UBP) (Baro Sensor) and Bluetooth-LowEnergy (BTLE).

In conventional implementations of LPP positioning sessions, LPPmessages may be sent by the location server and received by the UE asindependent LPP messages within an LPP location session. An LPP locationsession may typically comprise a number of LPP messages exchangedbetween the UE 105 and the LS (e.g. E-SMLC 132 or LMF 152) for thepurpose of transferring assistance data to UE 105 and/or determining alocation estimate for UE 105 (e.g. by the LS). Each LPP message maybelong to an LPP transaction and thus an LPP location session may alsocomprise one or more LPP transactions. When the purpose of an LPPlocation session has been achieved, or if some error or failure occurswhich prevents the purpose of an LPP location session from beingachieved, the LPP location session may be terminated (e.g. by the LS).Although the UE 105 can be aware of which LPP messages belong to thesame LPP transaction (e.g. via inclusion of the transaction ID in eachLPP message which may indicate a particular LPP transaction), the UE 105may not be unambiguously aware of which LPP messages belong to the sameLPP session. Accordingly, with conventional implementations of an LPPpositioning session, determining when a Network Initiated LPP sessionhas ended may not be possible by UE 105.

Accordingly, an enhancement to an existing LPP protocol may be used toindicate when one location session is different from another locationsession, when a location session has started and/or when a locationsession has ended. For example, in one technique, different correlationidentifiers (IDs) may be allocated by a network entity, such as MME 134or AMF 154, and included in one or more messages (e.g. NAS transportmessages used to transport LPP messages), which may be used to identifydifferent location sessions. For example, in this technique, the networkentity may allocate a different correlation ID for each new locationrequest for a UE 105 which is received from another entity (e.g. V-GMLC116 or GMLC 155). For example, the network entity may allocate acorrelation ID with a value of zero for a first location request for theUE 105, may then allocate a correlation ID with a value of one for asecond location request for the UE 105, may then further allocate acorrelation ID with a value of two for a third location request for theUE 105, and so on. The different correlation IDs may be allocated evenif earlier location requests have been completed and have ended. Forexample, if the first location request has a correlation ID of zero andhas already ended when the network entity receives the second locationrequest for UE 105, the network entity may still assign a correlation IDof one to the second location request. This may be needed as UE 105 maynot be aware that the LPP location session for the first locationrequest has ended, but, by detecting the different correlation ID forthe LPP location session for the second location request, UE 105 candetermine that this LPP location session is different, which may enableUE 105 to infer that the LPP location session for the first locationrequest has ended (e.g. following some timeout period of 10-20 secondsfor example). The correlation ID may be included by the network entityin all NAS transport messages sent to the UE 105 carrying an LPP messageas part of a location session to support this location request. Byobserving the correlation ID in received NAS transport messages carryingan LPP message, the UE 105 can be aware of which LPP message belong tothe same LPP session (due to being associated with the same correlationID) and which LPP messages belong to different LPP sessions (due tobeing associated with different correlation IDs).

In another technique, the location server (e.g. E-SMLC 132 or LMF 152)may assign a different session ID (also referred to as an LPP sessionID) for each location request for a target UE 105 received from anotherentity (e.g. MME 134, AMF 154, V-GMLC 116 or GMLC 155) and may includethe session ID in all LPP messages sent to the UE 105 as part of thesame LPP location session to obtain the requested location. By observingthe session ID in received LPP messages, the UE 105 can be aware ofwhich LPP message belong to the same LPP session (due to including thesame session ID) and which LPP messages belong to different LPP sessions(due to including different session IDs).

In another technique, the location server may include an indicator, suchas a “start session flag”, in the initial (e.g. first) LPP message sentto the UE 105 for a new location session S1 to indicate that the LPPmessage is the initial LPP message for the new location session S1. Inthis technique, a correlation ID or a session ID may also be sent withinor associated with each LPP message sent to the UE 105 for the locationsession S1 as described for the two previous techniques. However, unlikethe two previous techniques, the correlation ID or session ID may bedifferent to the correlation ID or session ID, respectively, for anyother LPP session ongoing at the same time as the session S1 but may notbe different to the correlation ID or session ID, respectively, for anLPP session S2 which either starts after session S1 has ended or endsbefore session S1 has started. Because of this, the UE 105 may notnormally be able to distinguish LPP messages for session S1 from LPPmessages for session S2. However, by observing the “start session flag”,the UE 105 may observe the start of session S1 (and may thereby concludethat a previous session S2 has ended) or may observe the start ofsession S2 (e.g. and may thereby conclude that a previous session S1 hasended).

In a further technique, the location server may additionally oralternatively provide an indicator, such as an “end session flag”, inthe final (e.g. last) LPP message sent by an LS to UE 105 for somelocation session. For example, in some embodiments, the final LPPmessage may be an LPP acknowledgement message sent by the LS in responseto (e.g.) an LPP Provide Location Information message sent to the LS bythe UE 105 to provide final location measurements or a locationestimate. In another example, the final LPP message may be an extra LPPmessage sent by the LS when the location session is known to have ended.As with the “start session flag”, the UE 105 may use the “end sessionflag” to determine that an ongoing location session has ended and thatany further LPP messages received from the LS which include or areassociated with a session ID or correlation ID which is the same as forthe location session which has ended are LPP messages for a new and thusdifferent location session.

In some implementations of communication system 200 of FIG. 2 andcommunication system 300 of FIG. 3, a location server may be included inNG-RAN 112, e.g. as part of a gNB 110 or separate from but connected toone or more gNBs 110. A location server in NG-RAN 112 may be referred toas a Location Management Component (LMC) or as a Local LMF. An LS inNG-RAN 112 may receive a location request for UE 105, e.g. from AMF 154via a gNB 110. The LS in NG-RAN 112 may then initiate an LPP locationsession with UE 105 to transfer assistance data to UE 105, obtainlocation measurements from UE 105 and/or obtain a location estimate forUE 105. The various techniques described herein to enable UE 105 to knowwhen an LPP location session has started and/or ended and to distinguishone LPP location session from another LPP location session may be usedfor an LPP location session between an LS in NG-RAN 112 and UE 105. Forexample, the procedure described for FIG. 4 may be applicable when LMF152 is replaced by an LS in NG-RAN 112.

FIG. 4 shows a signaling flow 400, applicable to communication system100, 200, or 300 shown in FIG. 1, 2, or 3, respectively, illustratingvarious enhancements to the LPP protocol to indicate when one locationsession is different from another location session (or when one locationsession has started or ended). Signaling flow 400 illustrates messagesexchanged between a UE 105 and a location server 402, which may be,e.g., E-SMLC 132 or LMF 152. It can be noted that here, messages areprovided in accordance with the 3GPP LPP protocol as an example.However, embodiments are not so limited (e.g. NPP or a combination ofLPP and LPPe, referred to as LPP/LPPe, might be used in anotherembodiment). The location server 402 may send and receive messages toand from the UE 105 (e.g. at actions 420, 425, 430, 435, 445, 447, 452and 465 described below) via one or more intermediate network entities,such as MME 134 or AMF 154.

At block 415, a location session may be initiated when the locationserver 402 receives a location request for the UE 105, e.g., from theExternal Client 150 via the GMLC 155, GMLCs 116 and 148 or 155V and 155Hand MME 134 or AMF 154. In one implementation, the location server 402may receive a correlation identifier (ID), e.g., allocated by the MME134 or AMF 154, with the location request to identify the locationsession, i.e., different correlation IDs are assigned to differentlocation sessions. In some implementations, the location server 402 maydetermine a session ID associated with the present location session.

At action 420, the location server 402 may optionally request capabilityinformation from the UE 105 by sending a LPP Request Capabilitiesmessage to the UE 105. The LPP Request Capabilities message, in someembodiments, may include a session indication. For example, the sessionindication in the LPP Request Capabilities message may be thecorrelation ID received in block 415, which specifically identifies thelocation session. In another implementation, the session indication maybe a session identification (ID), e.g., that may be determined by thelocation server 402 at block 415, that is specific to the presentlocation session. In some implementations, the session ID may beincluded in all LPP messages sent by the location server 402 to the UE105 to support the location request received at block 415 and possiblyin all LPP messages sent by the UE 105 to the location server 402 whichare sent in response to or otherwise associated with LPP messagescarrying the session ID sent by the location server 402 and received bythe UE 105. In another implementation, the LPP Request Capabilitiesmessage may include a new session indicator, such as a new session flag,that indicates that the LPP Request Capabilities message 415 is aninitial LPP message for a new location session. The session indication,e.g., correlation ID, session ID or a new session indicator, may beincluded as part of common Information Elements (IEs) in the LPP RequestCapabilities message.

At action 425, capability information is provided by UE 105 in an LPPProvide Capabilities message sent by the UE 105 to the location server402. The capability information may be provided by the UE 105 inresponse to the LPP Request Capabilities message or may be providedwithout a request, in which case action 420 may not occur. The LPPProvide Capabilities message from the UE 105 may be sent in accordancewith the LPP protocol providing various location-related capabilities ofUE 105, such as capabilities to support different position methods suchas Assisted GNSS (A-GNSS), OTDOA, RTK, Enhanced Cell ID (ECID), andsupport for different network measurements and assistance data etc.

At block 428, the location server 402 may determine one or more positionmethods to be used to locate the UE 105 and location assistance data tobe provided to the UE 105 based at least in part on the capabilityinformation received from the UE 105 at action 425. The location server402 may also determine preferred position methods and preferred positionmodes (e.g. UE based versus UE assisted positioning) for the UE 105based on the capability information provided by the UE 105.

At action 430, the location server 402 may send the UE 105 an LPPProvide Assistance Data (PAD) message, in response to receiving the LPPProvide Capabilities message at action 425 and determining the locationassistance data at block 428. The LPP Provide Assistance Data message,in some embodiments, may include a session indication. For example, theLPP Provide Assistance Data message may include the correlation ID,which may be assigned to the location session. In anotherimplementation, the LPP Provide Assistance Data message may include thesession ID, e.g., determined by the location server 402, that isspecific to the present location session. The session ID, for example,may be included in the LPP Provide Assistance Data message if the LPPRequest Capabilities message 420 previously provided the session ID orif the LPP Provide Assistance Data message 430 is the first message in alocation session. In another implementation, for example, where the LPPRequest Capabilities message 420 was not sent by the location server402, and the LPP Provide Assistance Data message is the first message ina location session, the LPP Provide Assistance Data may include a newsession indicator, such as a new session flag, that indicates that theProvide Assistance Data message 430 is for a new location session. Thesession indication, e.g., session ID or new session indicator, may beincluded as part of common IEs in the LPP Provide Assistance Datamessage. The PAD message may include the AD determined in block 428. TheAD provided in the LPP Provide Assistance Data message can becommensurate with the capabilities of the UE 105, as indicated in theLPP Provide Capabilities message. For example, if the UE 105 indicatesthat it is capable of obtaining location-related measurements for OTDOA,the location server 402 may provide a list of nearby cells (e.g. basedon a current serving cell or serving eNB 104 for the UE 105) andinformation (e.g. timing, frequency, bandwidth) for signals (e.g. PRS orCRS signals) transmitted within these cells by corresponding basestations (e.g. eNB 104 and eNB 106), which may enable RSTD measurementsby UE 105. Similarly, if UE 105 indicates support of A-GNSS in the LPPProvide Capabilities message sent at action 425, the location server 402may include information for visible SVs 190 in the LPP ProvideAssistance Data message sent at action 430. In one embodiment, action430 may be preceded by UE 105 sending an LPP Request Assistance Datamessage to location server 402 to request assistance data (not shown inFIG. 4).

At action 435, the location server 402 sends an LPP Request LocationInformation message to the UE 105. The LPP Request Location Informationmessage, in some embodiments, may include a session indication. Forexample, the LPP Request Location Information message may include thecorrelation ID, which may be assigned to the location session. Inanother implementation, the LPP Request Location Information message mayinclude the session ID, e.g., determined by the location server 402,that is specific to the present location session. The session ID, forexample, may be included in the LPP Request Location Information messageif the LPP Request Capabilities message 420 (and/or LPP ProvideAssistance Data message 430) previously provided the session ID or ifthe LPP Request Location Information message 435 is the first message ina location session. In another implementation, for example, where theLPP Request Capabilities message 420 and the LPP Provide Assistance Datamessage 430 were not sent by the location server 402, and the LPPRequest Location Information message is the first message in a locationsession, the LPP Request Location Information message may include a newsession indicator, such as a new session flag, that indicates that theLPP Request Location Information message 435 is for a new locationsession. The session indication, e.g., session ID or new sessionindicator, may be included as part of common IEs in the LPP RequestLocation Information message. The Request Location Information message435 from the location server 402 may request location-relatedmeasurements (e.g. measurements for A-GNSS, OTDOA and/or RTK). In someembodiments, the LPP Request Location Information message may requestthat UE 105 compute a location estimate from these measurements (e.g. ifthe position method is UE based OTDOA or UE based A-GNSS) and may alsoinclude a requested accuracy for any location measurements or locationestimate and/or a maximum response time. In some embodiments, the LPPRequest Location Information message may be a request for locationinformation for one or more position methods determined in block 428based on the capabilities information provided at action 425.

At block 440, the UE 105 may obtain the location information requestedat action 435. The location information, for example, may be locationrelated measurements obtained by UE 105 for RF signals transmitted bybase stations, such as eNBs 104 and 106 or gNBs 110, and/or SVs 190. Forexample, location related measurements may include measurements of RSTDobtained by measuring PRS or other reference signals (e.g. CRS signals)transmitted by base stations, measurements of RTT obtained by measuringsignals transmitted from and/or to the base stations, and/ormeasurements of pseudorange, code phase or carrier phase obtained bymeasuring one or more navigation signals transmitted by each of one ormore SVs 190. In some embodiments, UE 105 may also calculate a locationestimate based on the obtained location measurements. The UE 105 may useAD received at action 430 to help obtain the location measurementsand/or determine any location estimate.

At action 445, information indicative of one or more location-relatedmeasurements (e.g. a location estimate or the location measurements)obtained at block 440 is sent to the location server 402 by the UE 105in an LPP Provide Location Information message. The LPP Provide LocationInformation message may include any session indication received in theLPP Request Location Information sent at action 435.

At action 447, the location server 402 optionally sends an LPP Ackmessage acknowledging receipt of the Provide Location Informationmessage 445, which may be the final message in the first locationsession. The LPP Ack message sent at action 447 may include a sessionindication. For example, the LPP Ack message may include the correlationID, which may be assigned to the location session. In anotherimplementation, the LPP Ack message may include the session ID, e.g.,determined by the location server 402, that is specific to the presentlocation session. In another implementation, the session indication maybe an end session indicator, such as an end session flag, that indicatesthe end of the location session. The session indication, e.g., sessionID and/or end session indicator, may be included as part of common IEsin the LPP Ack message 447 or as part of an LPP message header.

At block 450, the location server 402 can use the location informationreceived at action 445 (comprising one or more location-relatedmeasurements or a location estimate) to determine (e.g. calculate orverify) an estimated location of the UE 105.

At action 452, the location server 402 may optionally send an extra LPPmessage with a session indication, e.g., indicating the end of thelocation session. For example, action 452 may occur if action 447 doesnot occur. For example, the extra LPP message 452 may include thecorrelation ID, which may be assigned to the location session. Inanother implementation, the extra LPP message 452 may include thesession ID, e.g., determined by the location server 402, that isspecific to the present location session. In another implementation, theextra LPP message 452 may include an end session flag (e.g. as part ofthe session indication), that indicates the end of the location session.

At block 455, the location server 402 may return the determined locationestimate (and any accompanying uncertainty or expected error, ifdetermined) to the requesting entity. If desired, block 455 may occurbefore or after action 452, if the extra LPP message is used.

At action 460, a new location session is initiated when the locationserver 402 receives a second location request for the UE 105, e.g., fromthe external client 150 via GMLC 155, the GMLCs 116 and 148 or 155V and155H and MME 134 or AMF 154. Action 460 may occur after action 415 andafter block 455 in some embodiments. Action 460 may occur after action415 but before block 455 in some other embodiments in which the firstand second location sessions may partly or completely overlap in time.Similar to the first location request 415, the second location request460 may include a correlation ID, e.g., allocated by the MME 134 or AMF154, that may be used to specifically identify the location session,i.e., the correlation ID in the first location request 415 and thesecond location request 460 are different. In some implementations, thelocation server 402 may determine a new session ID associated with thesecond location session, which is different than the session IDassociated with the first location session.

At action 465, the location server 402 may request capabilityinformation from the UE 105 for the new location session by sending aLPP Request Capabilities messages to the UE 105. As with the LPP RequestCapabilities message 420, the Request Capabilities message 465 mayinclude a session indication. For example, Request Capabilities message465 may include the new session ID, determined by the location server402 in block 460, that is different than the session ID included in thefirst Request Capabilities message 420. In another implementation, theRequest Capabilities message 465 may include a new session indicator,such as a new session flag, that indicates that the Request Capabilitiesmessage 465 is an initial LPP message for a new location session. Thesession indication, e.g., session ID or new session indicator, may beincluded as part of common IEs in the LPP Request Capabilities message.

At block 470, the UE 105 and location server 402 exchange LPP messagesfor the second location session and obtain the UE location, similar tothe messages, actions and blocks 425, 428, 430, 435, 440, 445, 447, 450,and 452 for the first location session. As discussed above, a sessionindication, such as a session ID for the second session, or new sessionflag for the second location session may be included in a RequestLocation Information message (e.g. if a Request Capabilities message 465is not sent by the location server 402). Further, an LPP Ack messagesent in response to an LPP message (e.g. an LPP Provide LocationInformation message) from the UE 105 may include a session indication,such as a session ID for the second session or an end session indicatorand/or an extra LPP message may be sent with a session indication, e.g.,indicating the end of the second session.

At block 475, the location server 402 may return the determined locationestimate (and any accompanying uncertainty or expected error, ifdetermined) for the second location session to the requesting entity.

FIG. 5 shows a signaling flow 500, applicable to communication system100, 200, or 300 shown in FIG. 1, 2, or 3, respectively, illustratinguse of a correlation ID as an enhancement to the LPP protocol toindicate when one location session is different from another locationsession. Signaling flow 500 illustrates messages exchanged between a UE105, base station 502, which may be, e.g., eNB 104, ng-eNB 114 or gNB110, a network entity 504, such as MME 134 or AMF 154, and a locationserver 506, which may be, e.g., E-SMLC 132 or LMF 152.

At block 510, the network entity 504 may receive a location request forthe UE 105, e.g., from the External Client 150 via the GMLC 155, theGMLCs 116 and 148 or the GMLCs 155V and 155H.

At block 515, the network entity 504 determines a correlation identifier(ID) for the present location session. Generally, a correlation ID isallocated by a network entity 504 such that it can be used to identifythe location server 506, e.g., E-SMLC 132 or LMF 152, serving thelocation session, the UE 105 and the location request received at block510. The network entity 504 may assign the correlation ID toadditionally identify the location session, e.g., where each differentlocation session is assigned a different correlation ID.

At action 520, the network entity 504 sends the location request, withthe correlation ID, to the location server 506 to initiate the locationsession.

At action 525, the location server 506 sends a transport message to thenetwork entity 504 (e.g. an LCS Application Protocol (LCS-AP) transportmessage for LTE access by UE 105) carrying the correlation ID and aDownlink (DL) LPP message, which may request location information fromthe UE 105, provide assistance data to the UE 105 or query for the UEcapabilities.

At block 530, if the UE 105 is not using Control Plane CIoT (CellularIoT) EPS Optimization and if the UE 105 is in ECM-IDLE state (e.g. if asignaling connection between UE 105 and network entity 504 and waspreviously released due to data and signaling inactivity), the networkentity 504 performs a network triggered service request in order toestablish or re-establish a signaling connection with UE 105.

If the UE 105 is using Control Plane CIoT EPS Optimization, proceduresfor Mobile Terminated Data Transport in Control Plane CIoT EPSoptimization may be performed by the network entity 504 at block 530 toestablish a signaling connection with the UE 105.

At action 535, the network entity 504 forwards the Downlink LPP messageto the UE 105 via the serving base station 502 in a NAS Transportmessage. The network entity 504 includes in the NAS transport message,the correlation ID associated with the present location session betweenthe network entity 504 and location server 506.

It should be understood that actions 525 and 535 (and block 530 ifperformed) may be equivalent to any of actions 420, 430 and 435, 447,and 452 shown in FIG. 4, which unlike FIG. 5, does not illustrate theintervening entities between the location server and UE, such as anetwork entity and base station. In addition, actions 525 and 535 may berepeated to send one or more additional DL LPP messages to UE 105.

At block 540, the UE 105 stores any assistance data if provided in theDownlink LPP message received from action 535 and performs anypositioning measurements and location computation if requested by theDownlink LPP message.

At block 545, if the UE 105 is not using Control Plane CIoT EPSOptimization and if the UE 105 is in ECM-IDLE state, the UE instigates aUE triggered service request or, when User Plane CIoT EPS optimizationapplies, a Connection Resume procedure in order to establish a signalingconnection with the network entity 504.

If the UE 105 is using Control Plane CIoT EPS Optimization, proceduresfor Mobile Originated Data Transport in Control Plane CIoT EPSoptimization may be performed by the UE 105 at block 545 to establish asignaling connection with the network entity 504.

At action 550, the UE 105 returns any location information obtained inblock 540 or may return any capabilities requested in the LPP message inaction 535 to the network entity 504 via the base station 502 in anUplink (UL) LPP message included in a NAS Transport message. The UplinkLPP message may alternatively carry a request for further assistancedata. The UE 105 also includes the correlation ID in the NAS TransportMessage that was received at action 535.

At action 555, the network entity 504 forwards the UL LPP message andthe correlation ID to the location server 506 in a transport message.Actions 550 and 555 may be repeated if the UE 105 needs to send multipleUL LPP messages to respond to the request received in action 535. Someor all of actions and blocks 525-555 may be repeated one or more timesas part of the location session between UE 105 and location server506—e.g. to enable UE 105 to request and location server 506 to returnassistance data to UE 105 or to allow location server 506 to request andUE 105 to return (e.g. additional) location measurements or a locationestimate to location server 506. A final repetition of actions 525 and535 (and possibly block 530) may be used by location server 506 to senda final DL LPP message to UE 105. The final DL LPP message may be asdescribed for action 447 or action 452 in FIG. 4.

At action 560, the location server 506 provides a location response(e.g. carrying any location estimate for UE 105 determined by locationserver 506), with the correlation ID, to the network entity 504, whichmay then forward the location estimate for UE 105, if received at action560, to the entity from which the location request was received at block510 (not shown in FIG. 5).

The signaling flow for actions and blocks 510-560 may be repeated for anew location session, for which a new correlation ID is assigned bynetwork entity 504 (different to the correlation ID used for actions520, 525 535, 550, 555 and 560), as illustrated in blocks 570, 575, 590and actions 580, 585 and 595 to send new assistance data, and to requestfurther location information and further UE capabilities.

FIG. 6 shows a process flow 600 illustrating a method for supportinglocation services for a user equipment (UE), such as the UE 105,performed by a location server, such as E-SMLC 132 or LMF 152, in whichenhancements to a positioning protocol, such as LPP, or a NAS Transportprotocol are used to indicate when one location session is differentfrom another location session (or when one location session has startedand/or ended). Process flow 600 may start at block 602, where an initialmessage for a first location session and a first indication of the firstlocation session are sent to a network entity, such as MME 134 or AMF154. For example, block 602 may be described at action 525 in FIG. 5 andmay correspond to one of actions 420, 430 or 435 in FIG. 4. The networkentity may send the initial message for the first location session andthe first indication of the first location session to the UE, e.g. asdescribed at action 535 in FIG. 5 and/or corresponding to one of actions420, 430 or 435 in FIG. 4.

At block 604, a final message for the first location session and asecond indication of the first location session are sent to the networkentity, e.g. as described for a final repetition of action 525 in FIG. 5and one of actions 447 and 452 in FIG. 4. The network entity may sendthe final message for the first location session and the secondindication of the first location session to the UE, e.g. as describedfor a final repetition of action 535 in FIG. 5 and as at one of actions447 and 452 in FIG. 4.

At block 606, an initial message for a second location session and anindication of the second location session are sent to the networkentity, wherein at least one of the second indication of the firstlocation session and the indication of the second location sessionindicate that the second location session is different from the firstlocation session. For example, block 606 may correspond to action 585 inFIG. 5 and/or to action 465 in FIG. 4. The network entity may send theinitial message for the second location session and the indication ofthe second location session to the UE, e.g. as for action 595 in FIG. 5and/or corresponding to action 465 in FIG. 4. The initial message forthe first location session, the final message for the first locationsession and the initial message for the second location session may eachbe an LPP message.

By way of example, the first indication of the first location sessionand the second indication of the first location session may be a firstcorrelation identifier (ID) and the indication of the second locationsession may be a second correlation ID, wherein the second correlationID is different from the first correlation ID, as described at block 515and 575 and actions 520, 525, 580, and 585 in FIG. 5 and at blocks 415and 460 and actions 420, 430, 435 and 465 in FIG. 4. The network entity,for example, may determine the first correlation ID and the secondcorrelation ID. The process may further include the location serverreceiving a first location request for the UE from the network entity,the first location request comprising the first correlation ID, asdescribed at block 415 and action 520 in FIGS. 4 and 5, and sending theinitial message for the first location session in response to receivingthe first location request, as described at actions 420, 430 or 435 andat action 525 in FIGS. 4 and 5. The process may further include thelocation server receiving a second location request for the UE from thenetwork entity, the second location request comprising the secondcorrelation ID, as described at block 460 and action 580 in FIGS. 4 and5, and sending the initial message for the second location session inresponse to receiving the second location request, as described atactions 465 and 585 in FIGS. 4 and 5.

In one implementation, the location server may determine a first sessionidentifier (ID), wherein the first indication of the first locationsession and the second indication of the first location session comprisethe first session ID, wherein the initial message for the first locationsession and the final message for the first location session comprisethe first session ID, as described for block 415 and actions 420, 447,and 452 in FIG. 4. The location server may determine a second sessionID, wherein the second session ID is different from the first sessionID, wherein the indication of the second location session comprises thesecond session ID, wherein the initial message for the second locationsessions comprises the second session ID, as described for block 460 andaction 465 in FIG. 4.

In one implementation, the first indication of the first locationsession may be an indication that the first location session is a newlocation session (or is the start of a new location session) asdescribed for action 420 in FIG. 4. In this implementation, theindication of the second location session may comprise an indicationthat the second location session is a new location session (or the startof a new location session), as described for action 465 in FIG. 4.

In one implementation, the second indication of the first locationsession may be an indication of an end of the first location session, asdescribed for actions 447 or 452 in FIG. 4. By way of example, the finalmessage of the first location session may be an acknowledgment message(e.g. an LPP acknowledgment message), as described for action 447 inFIG. 4.

FIG. 7 shows a process flow 700 illustrating a method for supportinglocation services for a user equipment (UE), such as the UE 105,performed by the UE, in which enhancements to a positioning protocol,such as LPP, or a NAS Transport protocol are used to indicate when onelocation session is different from another location session (or when onelocation session has started and/or ended). Process flow 700 may startat block 702, where an initial message for a first location session anda first indication of the first location session are received from anetwork entity, such as MME 134 or AMF 154. For example, block 702 maybe as described for action 535 in FIG. 5 and may correspond to one ofactions 420, 430 or 435 in FIG. 4. The network entity may receive theinitial message for the first location session and the first indicationof the first location session from a location server, such as E-SMLC 132or LMF 152, e.g., as described for action 525 in FIG. 5 and/orcorresponding to one of actions 420, 430 or 435 in FIG. 4.

At block 704, a final message for the first location session and asecond indication of the first location session are received from thenetwork entity, e.g. as described for a final repetition of action 535in FIG. 5 and/or corresponding to one of actions 447 and 452 in FIG. 4.The network entity may receive the final message for the first locationsession and the second indication of the first location session from alocation server (e.g. E-SMLC 132 or LMF 152), e.g. as described for afinal repetition of action 525 in FIG. 5 and/or corresponding to one ofactions 447 and 452 in FIG. 4.

At block 706, an initial message for a second location session and anindication of the second location session are received from the networkentity, wherein at least one of the second indication of the firstlocation session and the indication of the second location sessionindicate that the second location session is different from the firstlocation session, e.g. as described for actions and blocks 575-595 inFIG. 5 and/or corresponding to action 465 in FIG. 4. The network entitymay receive the initial message for the second location session and theindication of the second location session from the location server, e.g.corresponding to action 585 in FIG. 5 and/or action 465 in FIG. 4. Theinitial message for the first location session, the final message forthe first location session and the initial message for the secondlocation session may each be an LPP message a NAS Transport messagecontaining an LPP message.

By way of example, the first indication of the first location sessionand the second indication of the first location session may comprise afirst correlation identifier (ID), and the indication of the secondlocation session may comprise a second correlation ID, wherein thesecond correlation ID is different from the first correlation ID, asdescribed for blocks 515 and 575 and actions 520, 525, 580, and 585 inFIG. 5 and for blocks 415 and 460 and actions 420, 430 and 435 in FIG.4. The network entity, for example, may determine the first correlationID and the second correlation ID.

In one implementation, the first indication of the first locationsession and the second indication of the first location session maycomprise a first session identifier (ID) determined by a locationserver, such as E-SMLC 132 or LMF 152, wherein the initial message forthe first location session and the final message for the first locationsession comprise the first session ID, as described at block 415 andactions 420, 447, and 452 in FIG. 4. The indication of the secondlocation session may comprise a second session ID determined by thelocation server, wherein the second session ID is different from thefirst session ID, wherein the initial message for the second locationsession comprises the second session ID, as described for block 460 andaction 465 in FIG. 4.

In one implementation, the first indication of the first locationsession may be an indication that the first location session is a newlocation session (or the start of a new location session), and theindication of the second location session may comprise an indicationthat the second location session is a new location session (or the startof a new location session), as described for actions 420 and 465 in FIG.4.

In one implementation, the second indication of the first locationsession comprises an indication of an end of the first location session,as described for actions 447 or 452 in FIG. 4. By way of example, thefinal message of the first location session may be an acknowledgmentmessage (e.g. an LPP acknowledgment message), as described for action447 in FIG. 4.

FIG. 8 shows a process flow 800 illustrating a method for supportinglocation services for a user equipment (UE), such as the UE 105,performed by a network entity, such as MME 134 or AMF 154, in whichenhancements to a positioning protocol, such as LPP, or a NAS Transportprotocol are used to indicate when one location session is differentfrom another location session (or when one location session has startedand/or ended). Process flow 800 may start at block 802, where an initialmessage for a first location session for the UE and a first indicationof the first location session are received from a location server, suchas E-SMLC 132 or LMF 152. For example, block 802 may be as described ataction 525 in FIG. 5.

At block 804, the initial message for the first location session and thefirst indication of the first location session are sent to the UE, e.g.as described for action 535 in FIG. 5 and one of actions 420, 430 or 435in FIG. 4.

At block 806, a final message for the first location session and asecond indication of the first location session are received from thelocation server, e.g. as described for action 525 in FIG. 5 and/or oneof actions 447 and 452 in FIG. 4.

At block 808, the final message for the first location session and thesecond indication of the first location session are sent to the UE, e.g.as described for action 535 in FIG. 5 and one of actions 447 and 452 inFIG. 4.

At block 810, an initial message for a second location session for theUE and an indication of the second location session are received fromthe location server, e.g. corresponding to action 585 in FIG. 5 and/oraction 465 in FIG. 4.

At block 812, the initial message for the second location session andthe indication of the second location session are sent to the UE,wherein at least one of the second indication of the first locationsession and the indication of the second location session indicate thatthe second location session is different from the first locationsession, e.g. corresponding to action 595 in FIG. 5 and/or action 465 inFIG. 4. The initial message for the first location session, the finalmessage for the first location session and the initial message for thesecond location session may each be an LPP messages.

By way of example, the first indication of the first location sessionand the second indication of the first location session may comprise afirst correlation identifier (ID), and the indication of the secondlocation session may comprise a second correlation ID, wherein thesecond correlation ID is different from the first correlation ID, e.g.as described for blocks 515 and 575 and actions 520, 525, 580, and 585in FIG. 5 and/or for blocks 415 and 460 and actions 420, 430, 435 and465 in FIG. 4. The process may further include: receiving a firstlocation service request for the UE from another entity (e.g. V-GMLC 116or GMLC 155); determining the first correlation ID (e.g. as described atblock 515 in FIG. 5); sending a first location request for the UE to thelocation server, where the first location request comprises the firstcorrelation ID (e.g. as described for block 415 and action 520 in FIGS.4 and 5); and receiving the initial message for the first locationsession and the first correlation ID from the location server inresponse to the first location request (e.g. as described for action 420and action 525 in FIGS. 4 and 5). The process may further include:receiving a second location service request for the UE from anotherentity (e.g. V-GMLC 116 or GMLC 155) (e.g. as described for block 570 inFIG. 5); determining the second correlation ID (e.g. as described foraction 575 in FIG. 5); sending a second location request for the UE tothe location server, where the second location request comprises thesecond correlation ID (e.g. as described for block 460 and action 580 inFIGS. 4 and 5); and receiving the initial message for the secondlocation session and the second correlation ID from the location serverin response to the second location request (e.g. as described for action585 in FIG. 5).

In one implementation, the first indication of the first locationsession and the second indication of the first location session may be afirst session identifier (ID) determined by the location server, whereinthe initial message for the first location session and the final messagefor the first location session comprise the first session ID, asdescribed for block 415 and actions 420, 447, and 452 in FIG. 4. Theindication of the second location session may be a second session IDdetermined by the location server, wherein the second session ID isdifferent from the first session ID, wherein the initial message for thesecond location session comprises the second session ID, as describedfor block 460 and action 465 in FIG. 4.

In one implementation, the first indication of the first locationsession comprises an indication that the first location session is a newlocation session (or the start of a new location session), wherein theindication of the second location session comprises an indication thatthe second location session is a new location session (or the start of anew location session), as described for actions 420 and 465 in FIG. 4.

In one implementation, the second indication of the first locationsession comprises an indication of an end of the first location session,as described for action 447 or 452 in FIG. 4. By way of example, thefinal message of the first location session may be an acknowledgmentmessage (e.g. an LPP acknowledgment message), as described for action447 in FIG. 4.

FIG. 9 is a diagram illustrating an example of a hardware implementationof a location server 900, such as E-SMLC 132 shown in FIG. 1 or LMF 152shown in FIGS. 2 and 3, that is capable of using enhancements to apositioning protocol to indicate when one location session is differentfrom another location session. The location server 900 may be, e.g.,part of a wireless network such as a EPC shown in FIG. 1, a 5G Corenetwork (5GCN) shown in FIGS. 2 and 3, or an NG-RAN as shown in FIGS. 2and 3. The location server 900 includes, e.g., hardware components suchas an external interface 902, which may be a wired or wireless interfacecapable of connecting to a network entity, such as MME 134 or AMF 154.The external interface 902 may further be capable of connecting to othernetwork entities, such as a GMLC, such as GMLC 155, VGMLC 155V or HGMLC155H.

The location server 900 includes one or more processors 904 and memory910, which may be coupled together with bus 906. The one or moreprocessors 904 and other components of the location server 900 maysimilarly be coupled together with bus 906, a separate bus, or may bedirectly connected together or coupled using a combination of theforegoing. The memory 910 may store data and may contain executable codeor software instructions that when executed by the one or moreprocessors 904 cause the one or more processors 904 to operate as aspecial purpose computer programmed to perform the procedures andtechniques disclosed herein (e.g. such as the process flow 600).

As illustrated in FIG. 9, the memory 910 includes one or more componentsor modules that when implemented by the one or more processors 904implements the methodologies described herein. While the components ormodules are illustrated as software in memory 910 that is executable bythe one or more processors 904, it should be understood that thecomponents or modules may be dedicated hardware or firmware either inthe processors 904 or off processor. As illustrated, the memory 910 mayinclude a positioning unit 912 that when implemented by the one or moreprocessors 904 enables the one or more processors 904 to receive andsend messages pursuant to a desired positioning protocol, such as LPP,as illustrated in the signal flows shown in FIGS. 4 and 5. Thepositioning unit 912, for example, may enable the one or more processors904 receive location request messages, send initial messages and finalmessages for location sessions and to include correlation ID from anetwork entity and that are assigned to different location sessions fora UE.

The memory 910 may include a session ID unit 914 that when implementedby the one or more processors 904 enables the one or more processors 904to generate a new session ID for each location session, wherein one ormore of the messages sent pursuant to the positioning unit 912 mayinclude the generated session IDs, e.g., as part of common lEs in themessages.

The memory 910 may include a new session indicator unit 916 that whenimplemented by the one or more processors 904 enables the one or moreprocessors 904 to generate a new session indicator, such as a newsession flag, indicating when a new location session is initiated andthat is included in a first message in a new location session sentpursuant to the positioning unit 912.

The memory 910 may include an end session indicator unit 918 that whenimplemented by the one or more processors 904 enables the one or moreprocessors 904 to generate an end session indicator, such as an endsession flag, indicating when a location session is ending and that isincluded in a final message in a location session sent pursuant to thepositioning unit 912.

The memory 910 may further include a position determination unit 920that causes the one or more processors 904 to determine a location forthe UE using, at least in part, the location information received. Forexample, the position determination unit 920 may cause the one or moreprocessors 904 to determine an estimated location for the UE using thereceived location information by using one or more position methods,such as, for example, GNSS, Assisted GNSS (A-GNSS), Advanced ForwardLink Trilateration (AFLT), Observed Time Difference Of Arrival (OTDOA),WLAN or Enhanced Cell ID (ECID) or combinations thereof.

The methodologies described herein may be implemented by various meansdepending upon the application. For example, these methodologies may beimplemented in hardware, firmware, software, or any combination thereof.For a hardware implementation, the one or more processors may beimplemented within one or more application specific integrated circuits(ASICs), digital signal processors (DSPs), digital signal processingdevices (DSPDs), programmable logic devices (PLDs), field programmablegate arrays (FPGAs), processors, controllers, micro-controllers,microprocessors, electronic devices, other electronic units designed toperform the functions described herein, or a combination thereof.

For an implementation involving firmware and/or software, themethodologies may be implemented with modules (e.g., procedures,functions, and so on) that perform the separate functions describedherein. Any machine-readable medium tangibly embodying instructions maybe used in implementing the methodologies described herein. For example,software codes may be stored in a memory (e.g. memory 910) and executedby one or more processor units (e.g. processors 904), causing theprocessor units to operate as a special purpose computer programmed toperform the techniques and procedures disclosed herein. Memory may beimplemented within the processor unit or external to the processor unit.As used herein the term “memory” refers to any type of long term, shortterm, volatile, nonvolatile, or other memory and is not to be limited toany particular type of memory or number of memories, or type of mediaupon which memory is stored.

If implemented in firmware and/or software, the functions may be storedas one or more instructions or code on a non-transitorycomputer-readable storage medium. Examples include computer-readablemedia encoded with a data structure and computer-readable media encodedwith a computer program. Computer-readable media includes physicalcomputer storage media. A storage medium may be any available mediumthat can be accessed by a computer. By way of example, and notlimitation, such computer-readable media can comprise RAM, ROM, EEPROM,CD-ROM or other optical disk storage, magnetic disk storage,semiconductor storage, or other storage devices, or any other mediumthat can be used to store desired program code in the form ofinstructions or data structures and that can be accessed by a computer;disk and disc, as used herein, includes compact disc (CD), laser disc,optical disc, digital versatile disc (DVD), floppy disk and Blu-ray discwhere disks usually reproduce data magnetically, while discs reproducedata optically with lasers. Combinations of the above should also beincluded within the scope of computer-readable media.

In addition to storage on computer-readable storage medium, instructionsand/or data may be provided as signals on transmission media included ina communication apparatus. For example, a communication apparatus mayinclude a transceiver having signals indicative of instructions anddata. The instructions and data are stored on non-transitory computerreadable media, e.g., memory 910, and are configured to cause the one ormore processors (e.g. processors 904) to operate as a special purposecomputer programmed to perform the techniques and procedures disclosedherein. That is, the communication apparatus includes transmission mediawith signals indicative of information to perform disclosed functions.At a first time, the transmission media included in the communicationapparatus may include a first portion of the information to perform thedisclosed functions, while at a second time the transmission mediaincluded in the communication apparatus may include a second portion ofthe information to perform the disclosed functions.

Thus, a location server (e.g. a location server 900) capable ofsupporting location services for a user equipment (UE), may include ameans for sending an initial message for a first location session and afirst indication of the first location session to a network entity,which may be, e.g., the external interface 902 and one or moreprocessors 904 with dedicated hardware or implementing executable codeor software instructions in memory 910 such as the positioning unit 912,as well as the session ID unit 914, and new session indicator unit 916.A means for sending a final message for the first location session and asecond indication of the first location session to the network entity,which may be, e.g., the external interface 902 and one or moreprocessors 904 with dedicated hardware or implementing executable codeor software instructions in memory 910 such as the positioning unit 912,as well as the session ID unit 914, and end session indicator unit 918.A means for sending an initial message for a second location session andan indication of the second location session to the network entity,wherein at least one of the second indication of the first locationsession and the indication of the second location session indicate thatthe second location session is different from the first location sessionmay be, e.g., the external interface 902 and one or more processors 904with dedicated hardware or implementing executable code or softwareinstructions in memory 910 such as the positioning unit 912, as well asthe session ID unit 914, and new session indicator unit 916.

In one implementation, the first indication of the first locationsession and the second indication of the first location session may be afirst correlation identifier (ID) and the indication of the secondlocation session may be a second correlation ID, wherein the secondcorrelation ID is different from the first correlation ID, where thenetwork entity determines the first correlation ID and the secondcorrelation ID. The location server, for example, may include a meansfor receiving a first location request for the UE from the networkentity, the first location request comprising the first correlation ID,which may be, e.g., the external interface 902 and one or moreprocessors 904 with dedicated hardware or implementing executable codeor software instructions in memory 910 such as the positioning unit 912.A means for sending the initial message for the first location sessionin response to receiving the first location request may be, e.g., theexternal interface 902 and one or more processors 904 with dedicatedhardware or implementing executable code or software instructions inmemory 910 such as the positioning unit 912. A means for receiving asecond location request for the UE from the network entity, the secondlocation request comprising the second correlation ID may be, e.g., theexternal interface 902 and one or more processors 904 with dedicatedhardware or implementing executable code or software instructions inmemory 910 such as the positioning unit 912. A means for sending theinitial message for the second location session in response to receivingthe second location request, which may be the external interface 902 andone or more processors 904 with dedicated hardware or implementingexecutable code or software instructions in memory 910 such as thepositioning unit 912.

In one implementation, the location server may include a means fordetermining a first session identifier (ID), wherein the firstindication of the first location session and the second indication ofthe first location session comprise the first session ID, wherein theinitial message for the first location session and the final message forthe first location session comprise the first session ID, which may be,e.g., the one or more processors 904 with dedicated hardware orimplementing executable code or software instructions in memory 910 suchas the session ID unit 914. A means for determining a second session ID,wherein the second session ID is different from the first session ID,wherein the indication of the second location session comprises thesecond session ID, wherein the initial message for the second locationsessions comprises the second session ID may be, e.g., the one or moreprocessors 904 with dedicated hardware or implementing executable codeor software instructions in memory 910 such as the session ID unit 914.

FIG. 10 is a diagram illustrating an example of a hardwareimplementation of an UE 1000, such as UE 105 illustrated in FIGS. 1-3,that is capable of using enhancements to a positioning protocol (e.g.LPP) or a NAS Transport protocol to determine when one location sessionis different from another location session. The UE 1000 may include aWWAN transceiver 1002 to wirelessly communicate with, e.g., basestations or cellular transceivers such as one or more evolved Node B(e.g. eNB 104), a next generation eNB (e.g. ng-eNB 114), a New Radio(NR) Node B (e.g. a gNB 110). The UE 1000 may also include a WLANtransceiver 1004 to wirelessly communicate with local transceivers (e.g.WiFi APs or Bluetooth beacons). The UE 1000 may include one or moreantennas 1006 that may be used with the WWAN transceiver 1002 and WLANtransceiver 1004. The UE 1000 may further include a GNSS receiver 1008for receiving and measuring signals from GNSS SVs 190 (shown in FIGS.1-3). The UE 1000 may further include a user interface 1012 that mayinclude e.g., a display, a keypad or other input device, such as virtualkeypad on the display, through which a user may interface with the UE1000.

The UE 1000 further includes one or more processors 1014 and memory1020, which may be coupled together with bus 1016. The one or moreprocessors 1014 and other components of the UE 1000 may similarly becoupled together with bus 1016, a separate bus, or may be directlyconnected together or coupled using a combination of the foregoing. Thememory 1020 may store data and may contain executable code or softwareinstructions that when executed by the one or more processors 1014 causethe one or more processors 1014 to operate as a special purpose computerprogrammed to perform the techniques disclosed herein. As illustrated inFIG. 10, the memory 1020 may include one or more components or modulesthat may be implemented by the one or more processors 1014 to performthe methodologies described herein. While the components or modules areillustrated as software in memory 1020 that is executable by the one ormore processors 1014, it should be understood that the components ormodules may be dedicated hardware or firmware either in the one or moreprocessors 1014 or off the processors.

A number of software modules and data tables may reside in the memory1020 and be utilized by the one or more processors 1014 in order tomanage both communications and the functionality described herein. Itshould be appreciated that the organization of the contents of thememory 1020 as shown in FIG. 10 is merely exemplary, and as such thefunctionality of the modules and/or data structures may be combined,separated, and/or be structured in different ways depending upon theimplementation of the UE 1000.

As illustrated, the memory 1020 may include a positioning unit 1022 thatwhen implemented by the one or more processors 1014 enables the one ormore processors 1014 to receive and send messages pursuant to a desiredpositioning protocol, such as LPP, as illustrated in the signal flowsshown in FIGS. 4 and 5.

The memory 1020 may include a session identifier unit 1024 that whenimplemented by the one or more processors 1014 enables the one or moreprocessors 1014 to determine to which location session a receivedmessage pertains, e.g., based on a correlation ID, session ID, a newsession indicator or end session indicator present in one or moremessages received from a location server (e.g. E-SMLC 132 or LMF 152).

The memory 1020 may further include a location session module 1026 thatwhen implemented by the one or more processors 1014 configures the oneor more processors 1014 to engage in a location session with a locationserver as discussed herein, e.g., in signaling flows 400 and 500. Forexample, the location session module 1026 may include a capabilityinformation module 1028 that stores the capabilities of the UE 1000, andwhen implemented by the one or more processors 1014 configures the oneor more processors 1014 to transmit via the WWAN transceiver 1002 thecapability information to a location server, which may be transmitted,e.g., in response to receiving a request for capability information fromthe location server. The location session module 1026 in the memory 1020may further include a location assistance data module 1030 that whenimplemented by the one or more processors 1014 configures the one ormore processors 1014 to receive location assistance data from thelocation server. The location session module 1026 in the memory 1020 mayfurther include a location information module 1032 that when implementedby the one or more processors 1014 configures the one or more processors1014 to obtain, e.g., via one or more of the WWAN transceiver 1002, theWLAN transceiver 1004, and the GNSS receiver 1008, at least somelocation information. For example, the location information module 1032may include a measurement module 1034 that when implemented by the oneor more processors 1014 configures the one or more processors 1014 toobtain location measurements, such as may include measurements of RSTDobtained by measuring PRS or other reference signals (e.g. CRS signals)received by WWAN transceiver 1002 and/or WLAN transceiver 1004,measurements of RTT obtained by measuring signals received/transmittedby WWAN transceiver 1002 and/or WLAN transceiver 1004, and/ormeasurements of GNSS pseudorange, code phase or carrier phase obtainedby measuring one or more navigation signals received by GNSS receiver1008. The location information module 1032 may include an estimatemodule 1036 that when implemented by the one or more processors 1014configures the one or more processors 1014 to determine a locationestimate for the UE 1000, e.g., using the measurements obtained usingmeasurement module 1034. The location session module 1026 may furtherinclude a report module 1038 that transmits, e.g., via the WWANtransceiver 1002, at least some of the location information to thelocation server.

The methodologies described herein may be implemented by various meansdepending upon the application. For example, these methodologies may beimplemented in hardware, firmware, software, or any combination thereof.For a hardware implementation, the one or more processors 1014 may beimplemented within one or more application specific integrated circuits(ASICs), digital signal processors (DSPs), digital signal processingdevices (DSPDs), programmable logic devices (PLDs), field programmablegate arrays (FPGAs), processors, controllers, micro-controllers,microprocessors, electronic devices, other electronic units designed toperform the functions described herein, or a combination thereof.

For an implementation of UE 1000 involving firmware and/or software, themethodologies may be implemented with modules (e.g., procedures,functions, and so on) that perform the separate functions describedherein. Any machine-readable medium tangibly embodying instructions maybe used in implementing the methodologies described herein. For example,software codes may be stored in a memory (e.g. memory 1020) and executedby one or more processors 1014, causing the one or more processors 1014to operate as a special purpose computer programmed to perform thetechniques disclosed herein. Memory may be implemented within the one orprocessors 1014 or external to the one or more processors 1014. As usedherein the term “memory” refers to any type of long term, short term,volatile, nonvolatile, or other memory and is not to be limited to anyparticular type of memory or number of memories, or type of media uponwhich memory is stored.

If implemented in firmware and/or software, the functions performed byUE 1000 may be stored as one or more instructions or code on anon-transitory computer-readable storage medium such as memory 1020.Examples of storage media include computer-readable media encoded with adata structure and computer-readable media encoded with a computerprogram. Computer-readable media includes physical computer storagemedia. A storage medium may be any available medium that can be accessedby a computer. By way of example, and not limitation, suchcomputer-readable media can comprise RAM, ROM, EEPROM, CD-ROM or otheroptical disk storage, magnetic disk storage, semiconductor storage, orother storage devices, or any other medium that can be used to storedesired program code in the form of instructions or data structures andthat can be accessed by a computer; disk and disc, as used herein,includes compact disc (CD), laser disc, optical disc, digital versatiledisc (DVD), floppy disk and Blu-ray disc where disks usually reproducedata magnetically, while discs reproduce data optically with lasers.Combinations of the above should also be included within the scope ofcomputer-readable media.

In addition to storage on computer-readable storage medium, instructionsand/or data for UE 1000 may be provided as signals on transmission mediaincluded in a communication apparatus. For example, a communicationapparatus comprising part or all of UE 1000 may include a transceiverhaving signals indicative of instructions and data. The instructions anddata are stored on non-transitory computer readable media, e.g., memory1020, and are configured to cause the one or more processors 1014 tooperate as a special purpose computer programmed to perform thetechniques disclosed herein. That is, the communication apparatusincludes transmission media with signals indicative of information toperform disclosed functions. At a first time, the transmission mediaincluded in the communication apparatus may include a first portion ofthe information to perform the disclosed functions, while at a secondtime the transmission media included in the communication apparatus mayinclude a second portion of the information to perform the disclosedfunctions.

Thus, a user equipment, such as UE 1000, may include a means forreceiving an initial message for a first location session and a firstindication of the first location session from a network entity, whichmay be, e.g., the WWAN transceiver 1002 and one or more processors 1014with dedicated hardware or implementing executable code or softwareinstructions in memory 1020 such as the positioning unit 1022 andsession identifier unit 1024. A means for receiving a final message forthe first location session and a second indication of the first locationsession from the network entity, which may be, e.g., the WWANtransceiver 1002 and one or more processors 1014 with dedicated hardwareor implementing executable code or software instructions in memory 1020such as the positioning unit 1022 and session identifier unit 1024. Ameans for receiving an initial message for a second location session andan indication of the second location session from the network entity,wherein at least one of the second indication of the first locationsession and the indication of the second location session indicate thatthe second location session is different from the first location sessionmay be, e.g., the WWAN transceiver 1002 and one or more processors 1014with dedicated hardware or implementing executable code or softwareinstructions in memory 1020 such as the positioning unit 1022 andsession identifier unit 1024.

FIG. 11 is a diagram illustrating an example of a hardwareimplementation of a network entity 1100, such as MME 134 shown in FIG.1, or AMF 154 shown in FIGS. 2 and 3, that is capable of usingenhancements to a positioning protocol (e.g. LPP) or a NAS transportprotocol to indicate when one location session is different from anotherlocation session. The network entity 1100 includes, e.g., hardwarecomponents such as an external interface 1102, which may be a wired orwireless interface capable of connecting to a location server, such asE-SMLC 132 or LMF 152 shown in FIGS. 1-3, to an external client 150 viaa GMLC (e.g. a GMLC 155, V-GMLC 116 or H-GMLC 148), and to a UE 105, viabase stations or cellular transceivers such as one or more evolved NodeBs (e.g. eNB 104), a next generation eNB (e.g. ng-eNB 114), a New Radio(NR) Node B (e.g. a gNB 110).

The network entity 1100 further includes one or more processors 1104 andmemory 1110, which may be coupled together with bus 1106. The one ormore processors 1104 and other components of the network entity 1100 maysimilarly be coupled together with bus 1106, a separate bus, or may bedirectly connected together or coupled using a combination of theforegoing. The memory 1110 may store data and may contain executablecode or software instructions that when executed by the one or moreprocessors 1104 cause the one or more processors 1104 to operate as aspecial purpose computer programmed to perform the procedures andtechniques disclosed herein. As illustrated in FIG. 11, the memory 1110includes one or more components or modules that when implemented by theone or more processors 1104 implements the methodologies as describedherein. While the components or modules are illustrated as software inmemory 1110 that is executable by the one or more processors 1104, itshould be understood that the components or modules may be dedicatedhardware or firmware either in the processor or off processor.

As illustrated, the memory 1110 may include a location request unit1112, that when implemented by the one or more processors 1104 enablesthe one or more processors 1104 to receive a location request, e.g.,from an external client, via the external interface 1102. A correlationID unit 1114 when implemented by the one or more processors 1104 mayenable the one or more processors 1104 to allocate a correlation ID toidentify the location session associated with a received locationrequest, and may also identify the location server, e.g., E-SMLC 132 orLMF 152, to be used with the location session.

A message receive unit 1116 and a message send unit 1118 whenimplemented by the one or more processors 1104 enables the one or moreprocessors 1104 to receive messages and send messages, respectively, viathe external interface 1102, from and to a location server and a UE,during a positioning session using a desired positioning protocol, suchas LPP, as illustrated in the signal flows shown in FIGS. 4 and 5.

The methodologies described herein may be implemented by various meansdepending upon the application. For example, these methodologies may beimplemented in hardware, firmware, software, or any combination thereof.For a hardware implementation, the one or more processors may beimplemented within one or more application specific integrated circuits(ASICs), digital signal processors (DSPs), digital signal processingdevices (DSPDs), programmable logic devices (PLDs), field programmablegate arrays (FPGAs), processors, controllers, micro-controllers,microprocessors, electronic devices, other electronic units designed toperform the functions described herein, or a combination thereof.

For an implementation of network entity 1100 involving firmware and/orsoftware, the methodologies may be implemented with modules (e.g.,procedures, functions, and so on) that perform the separate functionsdescribed herein. Any machine-readable medium tangibly embodyinginstructions may be used in implementing the methodologies describedherein. For example, software codes may be stored in a memory (e.g.,memory 1110) and executed by one or more processors 1104, causing theone or more processors 1104 to operate as a special purpose computerprogrammed to perform the algorithms disclosed herein. Memory may beimplemented within the one or more processors 1104 or external to theone or more processors 1104. As used herein the term “memory” refers toany type of long term, short term, volatile, nonvolatile, or othermemory and is not to be limited to any particular type of memory ornumber of memories, or type of media upon which memory is stored.

If implemented in firmware and/or software, the functions performed bythe network entity 1100 may be stored as one or more instructions orcode on a non-transitory computer-readable storage medium such as memory1110. Examples include computer-readable media encoded with a datastructure and computer-readable media encoded with a computer program.Computer-readable media includes physical computer storage media. Astorage medium may be any available medium that can be accessed by acomputer. By way of example, and not limitation, such computer-readablemedia can comprise RAM, ROM, EEPROM, CD-ROM or other optical diskstorage, magnetic disk storage, semiconductor storage, or other storagedevices, or any other medium that can be used to store desired programcode in the form of instructions or data structures and that can beaccessed by a computer; disk and disc, as used herein, includes compactdisc (CD), laser disc, optical disc, digital versatile disc (DVD),floppy disk and Blu-ray disc where disks usually reproduce datamagnetically, while discs reproduce data optically with lasers.Combinations of the above should also be included within the scope ofcomputer-readable media.

In addition to storage on computer-readable storage medium, instructionsand/or data may be provided as signals on transmission media included ina communication apparatus. For example, a communication apparatuscomprising part or all of the network entity 1100 may include atransceiver having signals indicative of instructions and data. Theinstructions and data are stored on non-transitory computer readablemedia, e.g., memory 1110, and are configured to cause the one or moreprocessors 1104 to operate as a special purpose computer programmed toperform the procedures and techniques disclosed herein. That is, thecommunication apparatus includes transmission media with signalsindicative of information to perform disclosed functions. At a firsttime, the transmission media included in the communication apparatus mayinclude a first portion of the information to perform the disclosedfunctions, while at a second time the transmission media included in thecommunication apparatus may include a second portion of the informationto perform the disclosed functions.

Thus, a network entity, such as network entity 1100, may include a meansfor receiving an initial message for a first location session for a UE(e.g. UE 105) and a first indication of the first location session froma location server (e.g. E-SMLC 132 or LMF 152), which may be, e.g., theexternal interface 1102 and one or more processors 1104 with dedicatedhardware or implementing executable code or software instructions inmemory 1110 such as the message receive unit 1116. A means for sendingthe initial message for the first location session and the firstindication of the first location session to the UE may be, e.g., theexternal interface 1102 and one or more processors 1104 with dedicatedhardware or implementing executable code or software instructions inmemory 1110 such as the message send unit 1118. A means for receiving afinal message for the first location session and a second indication ofthe first location session from the location server may be, e.g., theexternal interface 1102 and one or more processors 1104 with dedicatedhardware or implementing executable code or software instructions inmemory 1110 such as the message receive unit 1116. A means for sendingthe final message for the first location session and the secondindication of the first location session to the UE may be, e.g., theexternal interface 1102 and one or more processors 1104 with dedicatedhardware or implementing executable code or software instructions inmemory 1110 such as the message send unit 1118. A means for receiving aninitial message for a second location session for the UE and anindication of the second location session from the location server maybe, e.g., the external interface 1102 and one or more processors 1104with dedicated hardware or implementing executable code or softwareinstructions in memory 1110 such as the message receive unit 1116. Ameans for sending the initial message for the second location sessionand the indication of the second location session to the UE, wherein atleast one of the second indication of the first location session and theindication of the second location session indicate that the secondlocation session is different from the first location session may be,e.g., the external interface 1102 and one or more processors 1104 withdedicated hardware or implementing executable code or softwareinstructions in memory 1110 such as the message send unit 1118.

In one implementation, the first indication of the first locationsession and the second indication of the first location session comprisea first correlation identifier (ID) and the indication of the secondlocation session comprises a second correlation ID, wherein the secondcorrelation ID is different from the first correlation ID. The networkentity may include a means for determining the first correlation ID,which may be, e.g., the one or more processors 1104 with dedicatedhardware or implementing executable code or software instructions inmemory 1110 such as the correlation ID unit 1114. A means for sending afirst location request for the UE to the location server, the firstlocation request comprising the first correlation ID may be, e.g., theexternal interface 1102 and one or more processors 1104 with dedicatedhardware or implementing executable code or software instructions inmemory 1110 such as the message send unit 1118. A means for receivingthe initial message for the first location session and the firstcorrelation ID from the location server in response to the firstlocation request may be, e.g., the external interface 1102 and one ormore processors 1104 with dedicated hardware or implementing executablecode or software instructions in memory 1110 such as the message receiveunit 1116. The network entity may further include a means fordetermining the second correlation ID which may be, e.g., the one ormore processors 1104 with dedicated hardware or implementing executablecode or software instructions in memory 1110 such as the correlation IDunit 1114. A means for sending a second location request for the UE tothe location server, the second location request comprising the secondcorrelation ID may be, e.g., the external interface 1102 and one or moreprocessors 1104 with dedicated hardware or implementing executable codeor software instructions in memory 1110 such as the message send unit1118. A means for receiving the initial message for the second locationsession and the second correlation ID from the location server inresponse to the second location request may be, e.g., the externalinterface 1102 and one or more processors 1104 with dedicated hardwareor implementing executable code or software instructions in memory 1110such as the message receive unit 1116.

One implementation (1) may be a method for supporting location servicesfor a user equipment (UE) performed by the UE, the method comprising:receiving an initial message for a first location session and a firstindication of the first location session from a network entity;receiving a final message for the first location session and a secondindication of the first location session from the network entity; andreceiving an initial message for a second location session and anindication of the second location session from the network entity,wherein at least one of the second indication of the first locationsession and the indication of the second location session indicate thatthe second location session is different from the first locationsession.

There may be some implementations (2) of the above-described method (1)wherein the first indication of the first location session and thesecond indication of the first location session comprise a firstcorrelation identifier (ID) and the indication of the second locationsession comprises a second correlation ID, wherein the secondcorrelation ID is different from the first correlation ID.

There may be some implementations (3) of the above-described method (2)wherein the network entity determines the first correlation ID and thesecond correlation ID.

There may be some implementations (4) of the above-described method (1)wherein: the first indication of the first location session and thesecond indication of the first location session comprise a first sessionidentifier (ID) determined by a location server, wherein the initialmessage for the first location session and the final message for thefirst location session comprise the first session ID; and the indicationof the second location session comprises a second session ID determinedby the location server, wherein the second session ID is different fromthe first session ID, wherein the initial message for the secondlocation session comprises the second session ID.

There may be some implementations (5) of the above-described method (1)wherein the first indication of the first location session comprises anindication that the first location session is a new location session,wherein the indication of the second location session comprises anindication that the second location session is a new location session.

There may be some implementations (6) of the above-described method (1)wherein the second indication of the first location session comprises anindication of an end of the first location session.

There may be some implementations (7) of the above-described method (6)wherein the final message of the first location session is anacknowledgment message.

There may be some implementations (8) of the above-described method (4)wherein the location server is an Enhanced Serving Mobile LocationCenter (E-SMLC) and the network entity is a Mobility Management Entity(MME).

There may be some implementations (9) of the above-described method (4)wherein the location server is a Location Management Function (LMF) andthe network entity is an Access and Mobility Management Function (AMF).

There may be some implementations (10) of the above-described method (1)wherein the initial message for the first location session, the finalmessage for the first location session and the initial message for thesecond location session are each a Long Term Evolution (LTE) PositioningProtocol (LPP) message or a Non-Access Stratum (NAS) Transport messagecontaining an LPP message.

One implementation (11) may be a user equipment (UE) for supportinglocation services for the UE, the UE comprising: at least one wirelesstransceiver configured to wirelessly communicate with at least onewireless network; memory configured to store instructions; and at leastone processor coupled to the at least one wireless transceiver and thememory, the at least one processor configured by the instructions storedin the memory to: receive via the at least one wireless transceiver aninitial message for a first location session and a first indication ofthe first location session from a network entity; receive via the atleast one wireless transceiver a final message for the first locationsession and a second indication of the first location session from thenetwork entity; and receive via the at least one wireless transceiver aninitial message for a second location session and an indication of thesecond location session from the network entity, wherein at least one ofthe second indication of the first location session and the indicationof the second location session indicate that the second location sessionis different from the first location session.

There may be some implementations (12) of the above-described UE (11)wherein the first indication of the first location session and thesecond indication of the first location session comprise a firstcorrelation identifier (ID) and the indication of the second locationsession comprises a second correlation ID, wherein the secondcorrelation ID is different from the first correlation ID.

There may be some implementations (13) of the above-described UE (12)wherein the network entity determines the first correlation ID and thesecond correlation ID.

There may be some implementations (14) of the above-described UE (11)wherein: the first indication of the first location session and thesecond indication of the first location session comprise a first sessionidentifier (ID) determined by a location server, wherein the initialmessage for the first location session and the final message for thefirst location session comprise the first session ID; and the indicationof the second location session comprises a second session ID determinedby the location server, wherein the second session ID is different fromthe first session ID, wherein the initial message for the secondlocation session comprises the second session ID.

There may be some implementations (15) of the above-described UE (11)wherein the first indication of the first location session comprises anindication that the first location session is a new location session,wherein the indication of the second location session comprises anindication that the second location session is a new location session.

There may be some implementations (16) of the above-described UE (11)wherein the second indication of the first location session comprises anindication of an end of the first location session.

There may be some implementations (17) of the above-described UE (16)wherein the final message of the first location session is anacknowledgment message.

There may be some implementations (18) of the above-described UE (14)wherein the location server is an Enhanced Serving Mobile LocationCenter (E-SMLC) and the network entity is a Mobility Management Entity(MME).

There may be some implementations (19) of the above-described UE (14)wherein the location server is a Location Management Function (LMF) andthe network entity is an Access and Mobility Management Function (AMF).

There may be some implementations (20) of the above-described UE (11)wherein the initial message for the first location session, the finalmessage for the first location session and the initial message for thesecond location session are each a Long Term Evolution (LTE) PositioningProtocol (LPP) message or a Non-Access Stratum (NAS) Transport messagecontaining an LPP message.

One implementation (21) may be a user equipment (UE) for supportinglocation services for the UE, the UE comprising: means for receiving aninitial message for a first location session and a first indication ofthe first location session from a network entity; means for receiving afinal message for the first location session and a second indication ofthe first location session from the network entity; and means forreceiving an initial message for a second location session and anindication of the second location session from the network entity,wherein at least one of the second indication of the first locationsession and the indication of the second location session indicate thatthe second location session is different from the first locationsession.

There may be some implementations (22) of the above-described UE (21)wherein the first indication of the first location session and thesecond indication of the first location session comprise a firstcorrelation identifier (ID) and the indication of the second locationsession comprises a second correlation ID, wherein the secondcorrelation ID is different from the first correlation ID.

There may be some implementations (23) of the above-described UE (22)wherein the network entity determines the first correlation ID and thesecond correlation ID.

There may be some implementations (24) of the above-described UE (21)wherein: the first indication of the first location session and thesecond indication of the first location session comprise a first sessionidentifier (ID) determined by a location server, wherein the initialmessage for the first location session and the final message for thefirst location session comprise the first session ID; and the indicationof the second location session comprises a second session ID determinedby the location server, wherein the second session ID is different fromthe first session ID, wherein the initial message for the secondlocation session comprises the second session ID.

One implementation (25) may be a non-transitory storage medium includingprogram code stored thereon, the program code is operable to configureat least one processor in a user equipment (UE) for supporting locationservices for the UE, comprising: program code to receive an initialmessage for a first location session and a first indication of the firstlocation session from a network entity; program code to receive a finalmessage for the first location session and a second indication of thefirst location session from the network entity; and program code toreceive an initial message for a second location session and anindication of the second location session from the network entity,wherein at least one of the second indication of the first locationsession and the indication of the second location session indicate thatthe second location session is different from the first locationsession.

There may be some implementations (26) of the above-describednon-transitory storage medium (25) wherein the first indication of thefirst location session and the second indication of the first locationsession comprise a first correlation identifier (ID) and the indicationof the second location session comprises a second correlation ID,wherein the second correlation ID is different from the firstcorrelation ID.

There may be some implementations (27) of the above-describednon-transitory storage medium (26) wherein the network entity determinesthe first correlation ID and the second correlation ID.

There may be some implementations (28) of the above-describednon-transitory storage medium (25) wherein: the first indication of thefirst location session and the second indication of the first locationsession comprise a first session identifier (ID) determined by alocation server, wherein the initial message for the first locationsession and the final message for the first location session comprisethe first session ID; and the indication of the second location sessioncomprises a second session ID determined by the location server, whereinthe second session ID is different from the first session ID, whereinthe initial message for the second location session comprises the secondsession ID.

One implementation (29) may be a method for supporting location servicesfor a user equipment (UE) performed by a network entity, the methodcomprising: receiving an initial message for a first location sessionfor the UE and a first indication of the first location session from alocation server; sending the initial message for the first locationsession and the first indication of the first location session to theUE; receiving a final message for the first location session and asecond indication of the first location session from the locationserver; sending the final message for the first location session and thesecond indication of the first location session to the UE; receiving aninitial message for a second location session for the UE and anindication of the second location session from the location server; andsending the initial message for the second location session and theindication of the second location session to the UE, wherein at leastone of the second indication of the first location session and theindication of the second location session indicate that the secondlocation session is different from the first location session.

There may be some implementations (30) of the above-described method(29) wherein the first indication of the first location session and thesecond indication of the first location session comprise a firstcorrelation identifier (ID) and the indication of the second locationsession comprises a second correlation ID, wherein the secondcorrelation ID is different from the first correlation ID.

There may be some implementations (31) of the above-described method(30) further comprising: determining the first correlation ID; sending afirst location request for the UE to the location server, the firstlocation request comprising the first correlation ID; receiving theinitial message for the first location session and the first correlationID from the location server in response to the first location request;determining the second correlation ID; sending a second location requestfor the UE to the location server, the second location requestcomprising the second correlation ID; and receiving the initial messagefor the second location session and the second correlation ID from thelocation server in response to the second location request.

There may be some implementations (32) of the above-described method(29) wherein: the first indication of the first location session and thesecond indication of the first location session comprise a first sessionidentifier (ID) determined by the location server, wherein the initialmessage for the first location session and the final message for thefirst location session comprise the first session ID; and the indicationof the second location session comprises a second session ID determinedby the location server, wherein the second session ID is different fromthe first session ID, wherein the initial message for the secondlocation session comprises the second session ID.

There may be some implementations (33) of the above-described method(29) wherein the first indication of the first location sessioncomprises an indication that the first location session is a newlocation session, wherein the indication of the second location sessioncomprises an indication that the second location session is a newlocation session.

There may be some implementations (34) of the above-described method(29) wherein the second indication of the first location sessioncomprises an indication of an end of the first location session.

There may be some implementations (35) of the above-described method(34) wherein the final message of the first location session is anacknowledgment message.

There may be some implementations (36) of the above-described method(29) wherein the location server is an Enhanced Serving Mobile LocationCenter (E-SMLC) and the network entity is a Mobility Management Entity(MME).

There may be some implementations (37) of the above-described method(29) wherein the location server is a Location Management Function (LMF)and the network entity is an Access and Mobility Management Function(AMF).

There may be some implementations (38) of the above-described method(29) wherein the initial message for the first location session, thefinal message for the first location session and the initial message forthe second location session are each a Long Term Evolution (LTE)Positioning Protocol (LPP) message.

One implementation (39) may be a network entity for supporting locationservices for a user equipment (UE) performed by the network entity, thenetwork entity comprising: an external interface configured tocommunicate with a wireless network; memory configured to storeinstructions; and at least one processor coupled to the externalinterface and the memory, the at least one processor configured by theinstructions stored in the memory to: receive via the external interfacean initial message for a first location session for the UE and a firstindication of the first location session from a location server; sendvia the external interface the initial message for the first locationsession and the first indication of the first location session to theUE; receive via the external interface a final message for the firstlocation session and a second indication of the first location sessionfrom the location server; send via the external interface the finalmessage for the first location session and the second indication of thefirst location session to the UE; receive via the external interface aninitial message for a second location session for the UE and anindication of the second location session from the location server; andsend via the external interface the initial message for the secondlocation session and the indication of the second location session tothe UE, wherein at least one of the second indication of the firstlocation session and the indication of the second location sessionindicate that the second location session is different from the firstlocation session.

There may be some implementations (40) of the above-described networkentity (39) wherein the first indication of the first location sessionand the second indication of the first location session comprise a firstcorrelation identifier (ID) and the indication of the second locationsession comprises a second correlation ID, wherein the secondcorrelation ID is different from the first correlation ID.

There may be some implementations (41) of the above-described networkentity (40) wherein the at least one processor is further configured to:determine the first correlation ID; send via the external interface afirst location request for the UE to the location server, the firstlocation request comprising the first correlation ID; receive via theexternal interface the initial message for the first location sessionand the first correlation ID from the location server in response to thefirst location request; determine the second correlation ID; send viathe external interface a second location request for the UE to thelocation server, the second location request comprising the secondcorrelation ID; and receive via the external interface the initialmessage for the second location session and the second correlation IDfrom the location server in response to the second location request.

There may be some implementations (42) of the above-described networkentity (39) wherein: the first indication of the first location sessionand the second indication of the first location session comprise a firstsession identifier (ID) determined by the location server, wherein theinitial message for the first location session and the final message forthe first location session comprise the first session ID; and theindication of the second location session comprises a second session IDdetermined by the location server, wherein the second session ID isdifferent from the first session ID, wherein the initial message for thesecond location session comprises the second session ID.

There may be some implementations (43) of the above-described networkentity (39) wherein the first indication of the first location sessioncomprises an indication that the first location session is a newlocation session, wherein the indication of the second location sessioncomprises an indication that the second location session is a newlocation session.

There may be some implementations (44) of the above-described networkentity (39) wherein the second indication of the first location sessioncomprises an indication of an end of the first location session.

There may be some implementations (45) of the above-described networkentity (44) wherein the final message of the first location session isan acknowledgment message.

There may be some implementations (46) of the above-described networkentity (39) wherein the location server is an Enhanced Serving MobileLocation Center (E-SMLC) and the network entity is a Mobility ManagementEntity (MME).

There may be some implementations (47) of the above-described networkentity (39) wherein the location server is a Location ManagementFunction (LMF) and the network entity is an Access and MobilityManagement Function (AMF).

There may be some implementations (48) of the above-described networkentity (39) wherein the initial message for the first location session,the final message for the first location session and the initial messagefor the second location session are each a Long Term Evolution (LTE)Positioning Protocol (LPP) message.

One implementation (49) may be a network entity for supporting locationservices for a user equipment (UE) performed by the network entity, thenetwork entity comprising: means for receiving an initial message for afirst location session for the UE and a first indication of the firstlocation session from a location server; means for sending the initialmessage for the first location session and the first indication of thefirst location session to the UE; means for receiving a final messagefor the first location session and a second indication of the firstlocation session from the location server; means for sending the finalmessage for the first location session and the second indication of thefirst location session to the UE; means for receiving an initial messagefor a second location session for the UE and an indication of the secondlocation session from the location server; and means for sending theinitial message for the second location session and the indication ofthe second location session to the UE, wherein at least one of thesecond indication of the first location session and the indication ofthe second location session indicate that the second location session isdifferent from the first location session.

There may be some implementations (50) of the above-described networkentity (49) wherein the first indication of the first location sessionand the second indication of the first location session comprise a firstcorrelation identifier (ID) and the indication of the second locationsession comprises a second correlation ID, wherein the secondcorrelation ID is different from the first correlation ID.

There may be some implementations (51) of the above-described networkentity (50) further comprising: means for determining the firstcorrelation ID; means for sending a first location request for the UE tothe location server, the first location request comprising the firstcorrelation ID; means for receiving the initial message for the firstlocation session and the first correlation ID from the location serverin response to the first location request; means for determining thesecond correlation ID; means for sending a second location request forthe UE to the location server, the second location request comprisingthe second correlation ID; and means for receiving the initial messagefor the second location session and the second correlation ID from thelocation server in response to the second location request.

There may be some implementations (52) of the above-described networkentity (49) wherein: the first indication of the first location sessionand the second indication of the first location session comprise a firstsession identifier (ID) determined by the location server, wherein theinitial message for the first location session and the final message forthe first location session comprise the first session ID; and theindication of the second location session comprises a second session IDdetermined by the location server, wherein the second session ID isdifferent from the first session ID, wherein the initial message for thesecond location session comprises the second session ID.

There may be some implementations (53) of the above-described networkentity (49) wherein the first indication of the first location sessioncomprises an indication that the first location session is a newlocation session, wherein the indication of the second location sessioncomprises an indication that the second location session is a newlocation session.

One implementation (54) may be a non-transitory storage medium includingprogram code stored thereon, the program code is operable to configureat least one processor in a network entity for supporting locationservices for a user equipment (UE), comprising: program code to receivean initial message for a first location session for the UE and a firstindication of the first location session from a location server; programcode to send the initial message for the first location session and thefirst indication of the first location session to the UE; program codeto receive a final message for the first location session and a secondindication of the first location session from the location server;program code to send the final message for the first location sessionand the second indication of the first location session to the UE;program code to receive an initial message for a second location sessionfor the UE and an indication of the second location session from thelocation server; and program code to send the initial message for thesecond location session and the indication of the second locationsession to the UE, wherein at least one of the second indication of thefirst location session and the indication of the second location sessionindicate that the second location session is different from the firstlocation session.

There may be some implementations (55) of the above-describednon-transitory storage medium (54) wherein the first indication of thefirst location session and the second indication of the first locationsession comprise a first correlation identifier (ID) and the indicationof the second location session comprises a second correlation ID,wherein the second correlation ID is different from the firstcorrelation

ID.

There may be some implementations (56) of the above-describednon-transitory storage medium (50) further comprising: program code todetermine the first correlation ID; program code to send a firstlocation request for the UE to the location server, the first locationrequest comprising the first correlation ID; program code to receive theinitial message for the first location session and the first correlationID from the location server in response to the first location request;program code to determine the second correlation ID; program code tosend a second location request for the UE to the location server, thesecond location request comprising the second correlation ID; andprogram code to receive the initial message for the second locationsession and the second correlation ID from the location server inresponse to the second location request.

There may be some implementations (57) of the above-describednon-transitory storage medium (54) wherein: the first indication of thefirst location session and the second indication of the first locationsession comprise a first session identifier (ID) determined by thelocation server, wherein the initial message for the first locationsession and the final message for the first location session comprisethe first session ID; and the indication of the second location sessioncomprises a second session ID determined by the location server, whereinthe second session ID is different from the first session ID, whereinthe initial message for the second location session comprises the secondsession ID.

There may be some implementations (58) of the above-describednon-transitory storage medium (54) wherein the first indication of thefirst location session comprises an indication that the first locationsession is a new location session, wherein the indication of the secondlocation session comprises an indication that the second locationsession is a new location session.

Reference throughout this specification to “one example”, “an example”,“certain examples”, or “exemplary implementation” means that aparticular feature, structure, or characteristic described in connectionwith the feature and/or example may be included in at least one featureand/or example of claimed subject matter. Thus, the appearances of thephrase “in one example”, “an example”, “in certain examples” or “incertain implementations” or other like phrases in various placesthroughout this specification are not necessarily all referring to thesame feature, example, and/or limitation. Furthermore, the particularfeatures, structures, or characteristics may be combined in one or moreexamples and/or features.

Some portions of the detailed description included herein are presentedin terms of algorithms or symbolic representations of operations onbinary digital signals stored within a memory of a specific apparatus orspecial purpose computing device or platform. In the context of thisparticular specification, the term specific apparatus or the likeincludes a general purpose computer once it is programmed to performparticular operations pursuant to instructions from program software.Algorithmic descriptions or symbolic representations are examples oftechniques used by those of ordinary skill in the signal processing orrelated arts to convey the substance of their work to others skilled inthe art. An algorithm is here, and generally, is considered to be aself-consistent sequence of operations or similar signal processingleading to a desired result. In this context, operations or processinginvolve physical manipulation of physical quantities. Typically,although not necessarily, such quantities may take the form ofelectrical or magnetic signals capable of being stored, transferred,combined, compared or otherwise manipulated. It has proven convenient attimes, principally for reasons of common usage, to refer to such signalsas bits, data, values, elements, symbols, characters, terms, numbers,numerals, or the like. It should be understood, however, that all ofthese or similar terms are to be associated with appropriate physicalquantities and are merely convenient labels. Unless specifically statedotherwise, as apparent from the discussion herein, it is appreciatedthat throughout this specification discussions utilizing terms such as“processing,” “computing,” “calculating,” “determining” or the likerefer to actions or processes of a specific apparatus, such as a specialpurpose computer, special purpose computing apparatus or a similarspecial purpose electronic computing device. In the context of thisspecification, therefore, a special purpose computer or a similarspecial purpose electronic computing device is capable of manipulatingor transforming signals, typically represented as physical electronic ormagnetic quantities within memories, registers, or other informationstorage devices, transmission devices, or display devices of the specialpurpose computer or similar special purpose electronic computing device.

In the preceding detailed description, numerous specific details havebeen set forth to provide a thorough understanding of claimed subjectmatter. However, it will be understood by those skilled in the art thatclaimed subject matter may be practiced without these specific details.In other instances, methods and apparatuses that would be known by oneof ordinary skill have not been described in detail so as not to obscureclaimed subject matter.

The terms, “and”, “or”, and “and/or” as used herein may include avariety of meanings that also are expected to depend at least in partupon the context in which such terms are used. Typically, “or” if usedto associate a list, such as A, B or C, is intended to mean A, B, and C,here used in the inclusive sense, as well as A, B or C, here used in theexclusive sense. In addition, the term “one or more” as used herein maybe used to describe any feature, structure, or characteristic in thesingular or may be used to describe a plurality or some othercombination of features, structures or characteristics. Though, itshould be noted that this is merely an illustrative example and claimedsubject matter is not limited to this example.

While there has been illustrated and described what are presentlyconsidered to be example features, it will be understood by thoseskilled in the art that various other modifications may be made, andequivalents may be substituted, without departing from claimed subjectmatter. Additionally, many modifications may be made to adapt aparticular situation to the teachings of claimed subject matter withoutdeparting from the central concept described herein.

Therefore, it is intended that claimed subject matter not be limited tothe particular examples disclosed, but that such claimed subject mattermay also include all aspects falling within the scope of appendedclaims, and equivalents thereof.

What is claimed is:
 1. A method for supporting location services for auser equipment (UE) performed by a location server, the methodcomprising: sending an initial message for a first location session anda first indication of the first location session to a network entity;sending a final message for the first location session and a secondindication of the first location session to the network entity; andsending an initial message for a second location session and anindication of the second location session to the network entity, whereinat least one of the second indication of the first location session andthe indication of the second location session indicate that the secondlocation session is different from the first location session.
 2. Themethod of claim 1, wherein the first indication of the first locationsession and the second indication of the first location session comprisea first correlation identifier (ID) and the indication of the secondlocation session comprises a second correlation ID, wherein the secondcorrelation ID is different from the first correlation ID.
 3. The methodof claim 2, wherein the network entity determines the first correlationID and the second correlation ID.
 4. The method of claim 3 furthercomprising: receiving a first location request for the UE from thenetwork entity, the first location request comprising the firstcorrelation ID; sending the initial message for the first locationsession in response to receiving the first location request; receiving asecond location request for the UE from the network entity, the secondlocation request comprising the second correlation ID; and sending theinitial message for the second location session in response to receivingthe second location request.
 5. The method of claim 1, furthercomprising: determining a first session identifier (ID), wherein thefirst indication of the first location session and the second indicationof the first location session comprise the first session ID, wherein theinitial message for the first location session and the final message forthe first location session comprise the first session ID; anddetermining a second session ID, wherein the second session ID isdifferent from the first session ID, wherein the indication of thesecond location session comprises the second session ID, wherein theinitial message for the second location sessions comprises the secondsession ID.
 6. The method of claim 1, wherein the first indication ofthe first location session comprises an indication that the firstlocation session is a new location session, wherein the indication ofthe second location session comprises an indication that the secondlocation session is a new location session.
 7. The method of claim 1,wherein the second indication of the first location session comprises anindication of an end of the first location session.
 8. The method ofclaim 7, wherein the final message of the first location session is anacknowledgment message.
 9. The method of claim 1, wherein the locationserver is an Enhanced Serving Mobile Location Center (E-SMLC) and thenetwork entity is a Mobility Management Entity (MME).
 10. The method ofclaim 1, wherein the location server is a Location Management Function(LMF) and the network entity is an Access and Mobility ManagementFunction (AMF).
 11. The method of claim 1, wherein the initial messagefor the first location session, the final message for the first locationsession and the initial message for the second location session are eacha Long Term Evolution (LTE) Positioning Protocol (LPP) message.
 12. Alocation server for supporting location services for a user equipment(UE), the location server comprising: an external interface configuredto communicate with a wireless network; memory configured to storeinstructions; and at least one processor coupled to the externalinterface and the memory, the at least one processor configured by theinstructions stored in the memory to: send via the external interface aninitial message for a first location session and a first indication ofthe first location session to a network entity; send via the externalinterface a final message for the first location session and a secondindication of the first location session to the network entity; and sendvia the external interface an initial message for a second locationsession and an indication of the second location session to the networkentity, wherein at least one of the second indication of the firstlocation session and the indication of the second location sessionindicate that the second location session is different from the firstlocation session.
 13. The location server of claim 12, wherein the firstindication of the first location session and the second indication ofthe first location session comprise a first correlation identifier (ID)and the indication of the second location session comprises a secondcorrelation ID, wherein the second correlation ID is different from thefirst correlation ID.
 14. The location server of claim 13, wherein thenetwork entity determines the first correlation ID and the secondcorrelation ID.
 15. The location server of claim 14, wherein the atleast one processor is further configured to: receive via the externalinterface a first location request for the UE from the network entity,the first location request comprising the first correlation ID; send viathe external interface the initial message for the first locationsession in response to receiving the first location request; receive viathe external interface a second location request for the UE from thenetwork entity, the second location request comprising the secondcorrelation ID; and send via the external interface the initial messagefor the second location session in response to receiving the secondlocation request.
 16. The location server of claim 12, wherein the atleast one processor is further configured to: determine a first sessionidentifier (ID), wherein the first indication of the first locationsession and the second indication of the first location session comprisethe first session ID, wherein the initial message for the first locationsession and the final message for the first location session comprisethe first session ID; and determine a second session ID, wherein thesecond session ID is different from the first session ID, wherein theindication of the second location session comprises the second sessionID, wherein the initial message for the second location sessionscomprises the second session ID.
 17. The location server of claim 12,wherein the first indication of the first location session comprises anindication that the first location session is a new location session,wherein the indication of the second location session comprises anindication that the second location session is a new location session.18. The location server of claim 12, wherein the second indication ofthe first location session comprises an indication of an end of thefirst location session.
 19. The location server of claim 18, wherein thefinal message of the first location session is an acknowledgmentmessage.
 20. The location server of claim 12, wherein the locationserver is an Enhanced Serving Mobile Location Center (E-SMLC) and thenetwork entity is a Mobility Management Entity (MME).
 21. The locationserver of claim 12, wherein the location server is a Location ManagementFunction (LMF) and the network entity is an Access and MobilityManagement Function (AMF).
 22. The location server of claim 12, whereinthe initial message for the first location session, the final messagefor the first location session and the initial message for the secondlocation session are each a Long Term Evolution (LTE) PositioningProtocol (LPP) message.
 23. A location server for supporting locationservices for a user equipment (UE), the location server comprising:means for sending an initial message for a first location session and afirst indication of the first location session to a network entity;means for sending a final message for the first location session and asecond indication of the first location session to the network entity;and means for sending an initial message for a second location sessionand an indication of the second location session to the network entity,wherein at least one of the second indication of the first locationsession and the indication of the second location session indicate thatthe second location session is different from the first locationsession.
 24. The location server of claim 23, wherein the firstindication of the first location session and the second indication ofthe first location session comprise a first correlation identifier (ID)and the indication of the second location session comprises a secondcorrelation ID, wherein the second correlation ID is different from thefirst correlation ID.
 25. The location server of claim 24, wherein thenetwork entity determines the first correlation ID and the secondcorrelation ID, the location server further comprising: means forreceiving a first location request for the UE from the network entity,the first location request comprising the first correlation ID; meansfor sending the initial message for the first location session inresponse to receiving the first location request; means for receiving asecond location request for the UE from the network entity, the secondlocation request comprising the second correlation ID; and means forsending the initial message for the second location session in responseto receiving the second location request.
 26. The location server ofclaim 23, further comprising: means for determining a first sessionidentifier (ID), wherein the first indication of the first locationsession and the second indication of the first location session comprisethe first session ID, wherein the initial message for the first locationsession and the final message for the first location session comprisethe first session ID; and means for determining a second session ID,wherein the second session ID is different from the first session ID,wherein the indication of the second location session comprises thesecond session ID, wherein the initial message for the second locationsessions comprises the second session ID.
 27. A non-transitory storagemedium including program code stored thereon, the program code isoperable to configure at least one processor in a location server forsupporting location services for a user equipment (UE), comprising:program code to send an initial message for a first location session anda first indication of the first location session to a network entity;program code to send a final message for the first location session anda second indication of the first location session to the network entity;and program code to send an initial message for a second locationsession and an indication of the second location session to the networkentity, wherein at least one of the second indication of the firstlocation session and the indication of the second location sessionindicate that the second location session is different from the firstlocation session.
 28. The non-transitory storage medium of claim 27,wherein the first indication of the first location session and thesecond indication of the first location session comprise a firstcorrelation identifier (ID) and the indication of the second locationsession comprises a second correlation ID, wherein the secondcorrelation ID is different from the first correlation ID.
 29. Thenon-transitory storage medium of claim 28, wherein the network entitydetermines the first correlation ID and the second correlation ID, thelocation server further comprising: program code to receive a firstlocation request for the UE from the network entity, the first locationrequest comprising the first correlation ID; program code to send theinitial message for the first location session in response to receivingthe first location request; program code to receive a second locationrequest for the UE from the network entity, the second location requestcomprising the second correlation ID; and program code to send theinitial message for the second location session in response to receivingthe second location request.
 30. The non-transitory storage medium ofclaim 27, further comprising: program code to determine a first sessionidentifier (ID), wherein the first indication of the first locationsession and the second indication of the first location session comprisethe first session ID, wherein the initial message for the first locationsession and the final message for the first location session comprisethe first session ID; and program code to determine a second session ID,wherein the second session ID is different from the first session ID,wherein the indication of the second location session comprises thesecond session ID, wherein the initial message for the second locationsessions comprises the second session ID.